Exemptions

• Many types of CMV operations are exempt from the regulations governing CMV parts & accessories and related requirements.

The types of operations that are exempt from the Federal Motor Carrier Safety Regulations (FMCSRs), including the vehicle specifications in Parts 325 (Interstate Motor carrier Noise Emission Standards), 393 (Parts and Accessories Necessary for Safe Operation), and 399 (Employee Safety and Health Standards), are described in 390.3(f):

• All school bus operations (between home and school), as defined in 390.5;
• Transportation performed by the federal government or a state or local government (but not including contractors doing work for the government);
• The occasional transportation of personal property by individuals when there is no compensation involved and the transportation is not business-related;
• The transportation of human corpses or sick and injured persons;
• The operation of fire trucks and rescue vehicles while involved in emergency and related operations;
• The operation of commercial motor vehicles (CMVs) designed to transport between 9 and 15 passengers (including the driver), not for direct compensation (these operations are not completely exempt from the FMCSRs, however); and
• Drivers of vehicles used to respond to a pipeline emergency or used primarily to transport propane winter heating fuel, but only if the regulations prevent the driver from responding to an emergency condition requiring immediate response.

Pipeline welding truck exemption

Under 390.38, certain pipeline welding trucks, including the employer and operator, are exempt from the regulations governing parts and accessories and inspection and maintenance (Part 393 and Part 396).

A “pipeline welding truck” is defined in 390.38(b) as a motor vehicle that is traveling in the state in which the vehicle is registered or another state, is owned by a welder, is a pick-up style truck, is equipped with a welding rig that is used in the construction or maintenance of pipelines and has a gross vehicle weight and combination weight rating and weight of 15,000 pounds or less.

Lights, reflectors, and electrical equipment

• The FMCSRs specify the quantity, color, location, and position of lighting and reflective devices on motor vehicles.
• The FMVSS list the manufacturing specifications for original and replacement lamps, reflective devices, and associated equipment, including some technical data related to the location of certain lights and reflectors.
• All lamps must be securely attached, capable of being operated at all times, and not obscured by the tailboard, any part of the load, dirt, or other added vehicle or work requirement.

The purpose of the roadway illumination and vehicle conspicuity requirements are to:

• Reduce traffic accidents, injuries, and death by providing adequate illumination of the roadway.
• Enhance the visibility or attention-getting ability so that motor vehicles are seen and their signals clearly understood by other motorists and pedestrians, in both daylight and darkness (or any other conditions that might reduce visibility).

Applicable regulations

In general, the Federal Motor Carrier Safety Regulations (FMCSR) in Part 393 specify the quantity, color, location, and position of lighting and reflective devices on motor vehicles, while the Federal Motor Vehicle Safety Standards (FMVSS) in Part 571 list the manufacturing specifications for original and replacement lamps (including bulbs), reflective devices, and all associated equipment. Part 571 also provides some technical data related to the location of some lights and reflectors. This is achieved by 393.11 referencing 571.108 and stating that the vehicle must meet the applicable 571.108 standard that was in place at time of manufacture.

Lamps operable, obstructions prohibited

In general, all lamps must be securely attached and capable of being operated at all times. In addition, lamps and reflective devices must not be obscured by the tailboard, any part of the load, dirt, or other added vehicle or work equipment. However, the conspicuity treatments (i.e., retroreflective sheeting or reflex reflectors) on the front-end protection devices may be obscured by part of the load being transported. (393.9) In addition, all lighting devices must meet the requirements of Part 571 and the associated Society of Automotive Engineers (SAE) standards (when referenced).

List of required lighting and reflective devices

Table 1 in 393.11 contains a list of the various lighting and reflective devices required by 393.11 and the specifications as described in 571.108. The device specifications include quantity, color, location, position, height above the road surface, and the vehicles for which the device is required. The device list includes:

• Headlamps
• Turn signal (front/rear)
• Identification lamps (front/rear)
• Tail lamps
• Stop lamps
• Clearance lamps
• Reflex reflector, intermediate (side)
• Reflex reflector (rear/rear side/front side)
• License plate lamp (rear)
• Side marker lamp (front/intermediate/rear)
• Vehicular hazard warning signal flasher lamps
• Backup lamp
• Parking lamp

Reflective tape and reflectors

• The FMCSRs specify requirements for reflective tape and/or reflectors on certain trailers and truck tractors.
• Tape and reflectors are not required on straight trucks.

The FMCSRs require the use of “conspicuity” materials — that is, reflective tape and/or reflex reflectors — on certain trailers and the rear of truck tractors, to help make these vehicles more visible to other motorists at night or when visibility is otherwise reduced. The following is an overview of the basic requirements.

Trailers

The conspicuity requirements apply to semitrailers and trailers that have an overall width of 80 inches or more and a gross vehicle weight rating (GVWR) of 10,001 pounds or more. Trailers manufactured on or after December 1, 1993, were to be manufactured with the proper conspicuity treatments as described in 571.108. Those manufactured prior to that date were to be retrofitted to meet the same standards, although a certain amount of flexibility is allowed (see 393.13).

Tractors

Truck tractors manufactured on or after July 1, 1997, must be equipped with red-and-white reflective material (tape or reflectors) similar to that required on the rear of the trailers they tow, to increase nighttime conspicuity. This includes white reflective material marking the upper corners of the cab (as described for trailers above) and red-and-white material marking the width of the body, normally installed on the mudflaps, as follows:

• Two strips of sheeting or reflectors, each at least 24 inches long, must be located as close as possible to the edges of the rear fenders, mudflaps, or the mudflap support brackets.
• The strips must be mounted as horizontal as possible on the mudflap support brackets, on plates attached to the mudflap support brackets, or on the mudflaps.
• Strips on mudflaps must be mounted no lower than 12 inches below the upper horizontal edge of the mudflap.
• If the vehicle is delivered with temporary mudflap support brackets, the strips must be mounted on the mudflaps or on plates transferable to the permanent mudflap support brackets.

Straight trucks

The requirements for reflective tape do not apply to straight trucks, only truck tractors and large trailers as noted above. Tape and reflectors may be added to straight trucks as an added measure of safety as long as they do not conflict with any required lights.

LED lights

• While LED lights are used by many carriers due to reliability, no official rules have been issued on when an LED light with failed diodes must be replaced.
• Some officers will write a citation on an LED light if there is a “dark area” on the lens due to diode(s) not functioning.
• Many states require officers to look at the light and, if it is still clearly visible from 500 feet away, then no citation is written.

Many carriers have decided to go with light emitting diode (LED) lights for several reasons, the main one being reliability. However, an ongoing issue with LED lights is defective diodes within the bulb. The problem arises due to the fact that there have been no official interpretations published by the Federal Motor Carrier Safety Act (FMCSA) or the National Highway Traffic Safety Act (NHTSA) on when an LED light with failed diodes must be replaced. Therefore, officers decide, based on various factors, whether to write a citation for an LED light with diodes out.

The manufacturers state that if enough diodes are out that the candlepower requirements cannot be met across the entire face of the bulb, it must be replaced (the candlepower requirements are in 571.108). Using this information, officers take one of two approaches:

• Some officers will write up the light if there is a “dark area” on the lens due to diode(s) not functioning. In some models, this means that one diode being out (in a five or six diode bulb) could result in the light being written up.
• Other officers will look at the light and judge whether it is still clearly visible as the type of light it is supposed to be from 500 feet away. While not directly used in the federal regulations, the 500-foot standard is how many states’ traffic codes determine if the candlepower requirements are being met.

Canadian standard: Canada, on the other hand, does have a requirement. Canada’s national safety standards state that once 25 percent of the diodes are not functioning, the light is to be “rejected” as a working light.

Brakes

• All wheels on a CMVs must be equipped with operative brakes adequate to stop and hold the vehicle or combination of motor vehicles.
• Each CMV must meet the applicable service, parking, and emergency brake requirements.
• The requirement that a CMV be equipped with operative brakes on all wheels also applies to any motor vehicle towed by means of a tow-bar when another motor vehicle is full-mounted on the towed vehicle, and any saddlemount configuration with a fullmount.

One of the essential parts necessary for the safe operation of a commercial motor vehicle (CMV) under the Federal Motor Carrier Safety Regulations (FMCSRs) is brakes.

Required brake systems

Every CMV must have operative brakes adequate to stop and hold the vehicle or combination of motor vehicles. Each CMV must meet the applicable service, parking, and emergency brake requirements. (393.40; 393.48).

Service brake systems — The service brakes requirements, found in 393.40(b), include rules for the following braking systems:

• Hydraulic
• Air
• Vacuum
• Electric
• Surge

Parking brake systems — Each CMV must be equipped with a parking brake system that meets the applicable requirements of 393.41. (393.40(c))

Emergency brakes — The emergency brake regulations, found in 393.40(d), are broken down into two categories: (1) partial failure of service brakes, and (2) vehicles manufactured on or after July 1, 1973.

• Partial failure of service brakes:
  • Hydraulic brake systems — Motor vehicles manufactured on or after September 2, 1983, and equipped with a split service brake system must, at a minimum, meet the partial failure requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 105 in effect on the date of manufacture.
  • Air brake systems — Buses, trucks and truck tractors manufactured on or after March 1, 1975, and trailers manufactured on or after January 1, 1975, must be equipped with an emergency brake system which, at a minimum, meets the requirements of FMVSS No. 121 in effect on the date of manufacture.
  • Vehicles not subject to FMVSS Nos. 105 and 121 on the date of manufacture — Buses, trucks and truck tractors not subject to FMVSS Nos. 105 or 121 on the date of manufacture must meet the requirements of 393.40(e). Trailers not subject to FMVSS No. 121 at the time of manufacture must meet the requirements of 393.43.
• Vehicles manufactured on or after July 1, 1973:
  • A bus, truck, truck tractor, or a combination of motor vehicles manufactured on or after July 1, 1973, and not a hydraulic or air brake system, must have an emergency brake system which consists of emergency features of the service brake system or an emergency system separate from the service brake system.
  • A control by which the driver applies the emergency brake system must be located so that the driver can operate it from the normal seating position while restrained by any seat belts with which the vehicle is equipped. The emergency brake control may be combined with either the service brake control or the parking brake control, but all three controls may not be combined.

Brakes required on all wheels

Every CMV must be equipped with brakes acting on all wheels. This requirement also applies to:

1. Any motor vehicle towed by means of a tow-bar when another motor vehicle is full-mounted on the towed vehicle; and
2. Any saddlemount configuration with a fullmount. (393.42)

Windows and windshields

• The glazing material (laminated glass) used in windshields, windows, and doors on a motor vehicles manufactured on or after December 25, 1968, must meet or exceed the federal requirements in effect at the time of the vehicle’s manufacture
• Each windshield must be free of discoloration or damage in the area extending upward from the height of the top of the steering wheel (excluding a two inch border at the top of the windshield) and extending from a one inch border at each side of the windshield or the windshield panel.
• Devices mounted on the interior of the windshield, except for vehicle safety technologies, must not be mounted more than six inches below the upper edge of the windshield, outside the area swept by the windshield wipers, and outside the driver’s sight lines to the road and highway signs and signals.

Each bus, truck and truck-tractor must have a windshield. Each windshield or portion of a multi-piece windshield must be mounted using the full periphery of the glazing (laminated glass) material. (393.60(b))

Each truck and truck tractor (except trucks engaged in armored car service) must have at least one window on each side of the driver’s compartment. The minimum size and configuration requirements for the side windows are set forth in 393.61.

Glazing (laminated glass) material

The glazing material (laminated glass) used in windshields, windows, and doors on a motor vehicle manufactured on or after December 25, 1968, must meet or exceed the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 205 in effect on the date of manufacture of the motor vehicle. The glass must be marked in accordance with FMVSS No. 205 ( 571.205, S6). (393.60(a))

Windshield condition

Except for certain exceptions set forth below, each windshield must be free of discoloration or damage in the area extending upward from the height of the top of the steering wheel (excluding a two inch border at the top of the windshield) and extending from a one inch border at each side of the windshield or the windshield panel. Exceptions:

1. Coloring or tinting of windshields and windows. (393.60(d))
2. Any crack that is not intersected by any other cracks.
3. Any damaged area which can be covered by a 3/4 inch disc if not closer than three inches to any other similarly damaged area. (393.60(c))

Coloring or tinting of windshields and windows

The coloring or tinting of windshields and the windows to the immediate right and left of the driver is allowed. The parallel luminous transmittance through the colored or tinted glazing may not be less than 70 percent of the light at normal incidence in those portions of the windshield or windows which are marked as having a parallel luminous transmittance of not less than 70 percent. The transmittance restriction does not apply to other windows on the commercial motor vehicle. (393.60(d))

Obstructions to the driver’s field of view

Devices mounted on the interior of the windshield — Antennas, and similar devices must not be mounted more than six inches below the upper edge of the windshield, outside the area swept by the windshield wipers, and outside the driver’s sight lines to the road and highway signs and signals.

Exception: This rule, however, does not apply to vehicle safety technologies mounted on the interior of a windshield. Devices with vehicle safety technologies must be mounted outside the driver’s sight lines to the road and to highway signs and signals, and: (1) not more than 8.5 inches below the upper edge of the area swept by the windshield wipers; or (2) not more than 7 inches above the lower edge of the area swept by the windshield wipers. (393.60(e)(1))

Decals and stickers mounted on the windshield — Commercial Vehicle Safety Alliance (CVSA) inspection decals, and stickers or decals required under federal or state laws may be placed at the bottom or sides of the windshield provided they do not extend more than 4 1/2 inches from the bottom of the windshield, are located outside the area swept by the windshield wipers, and outside the driver’s sight lines to the road and highway signs or signals. (393.60(e)(2))

Fuel systems

• While there are certain rules common to all types of fuel systems, liquid fuel tanks, CNG fuel containers, and LPG systems all have specific requirements over and above the general fuel system rules.
• The rules applicable to all fuel systems include the installation and location of the fuel tank, a prohibition against gravity or syphon feeds, the location of selection control valves, fuel lines, and excess flow valves.
• If switching to an alternate fuel vehicle, carriers must make sure that technicians and drivers receive training on safely fueling the new vehicles and how to handle any fuel-related incidents, such as a safety/pressure relief valve opening and when (and how) to operate the emergency fuel shut-offs.

The regulations for all types of fuel systems, including liquid fuel tanks, compressed natural gas (CNG) fuel containers, and liquefied petroleum gas systems are found in Part 393, Subpart E.

All fuel systems

The common requirements applicable to all fuel systems include:

• Location of the fuel tank
• Fuel tank installation
• Prohibition against gravity or syphon feeds
• Location of selection control valves
• Fuel lines
• Excess flow valves (393.65)

Liquid fuel tanks

The rules for liquid fuel tanks apply to tanks containing or supplying fuel for the operation of commercial motor vehicles (CMVs) or for the operation of auxiliary equipment installed on, or used in connection with CMVs. The rules set forth the requirements for the construction of liquid fuel tanks, performance tests for liquid fuel tanks and side-mounted liquid fuel tanks, and manufacturer certifications and markings. (393.67)

CNG fuel containers

Fuel containers used to supply CNG for the operation of CMVs or for the operation of auxiliary equipment installed on or used in connection with CMVs must comply with 393.68.

Specifically, any motor vehicle manufactured on or after March 26, 1995, and equipped with a CNG fuel tank must meet the CNG container requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 304 (571.304) in effect at the time of manufacture of the vehicle.

In addition, each CNG fuel container must be permanently labeled in accordance with the requirements of FMVSS No. 304, S7.4, which mandates affixation of a decal informing the vehicle owner and operator of the 36,000 mile or annual (whichever comes first) tank inspection requirement.

Liquefied petroleum gas systems

Motor vehicles, or auxiliary equipment installed on, or used in connection with, a motor vehicle that uses liquefied petroleum gas (LPG) as a fuel must conform to certain Editions or Divisions of the “Standards for the Storage and Handling of Liquefied Petroleum Gases” of the National Fire Protection Association, Battery March Park, Quincy, MA 02269, based on the date of installment of the system. An LPG fuel system subject to a specific Edition of the standards may also conform to the applicable provisions in a later Edition of the standards. The tank of a LPG fuel system must be marked to indicate that the system conforms to the standards. (393.69)

Alternate fuel considerations

If a carrier is considering switching to an alternate fuel vehicle, there are several considerations:

• First, it will need to get at least some of its technicians trained to inspect and maintain the fuel system. Some original equipment manufacturers (OEMs) and parts suppliers provide the training.
• Second, it will need to begin stocking parts for the systems.
• Third, if it is a gaseous fuel (such as CNG or LNG), it will need to make modifications to its facilities to prevent the collection of flammable gases and the accidental ignition of gases (in case of a leak in the building).
• Finally, it will need to establish a preventive maintenance inspection schedule for the fuel system.

Discussing the specifications and maintenance requirements with the system provider (OEM or parts supplier) can provide insight into the inspection and parts requirements. Also, do not forget that the technicians (and drivers!) will need to be trained on safely fueling these vehicles and how to handle any fuel-related incidents, such as a safety/pressure relief valve opening and when (and how) to operate the emergency fuel shut-offs.

Coupling devices

• The rules governing coupling devices and towing methods provide the requirements for vehicle tracking, fifth wheel assemblies, towing of full trailers, and safety devices in case of tow-bar failure or disconnection.
• A tow-bar must be structurally adequate for the weight being drawn, be properly and securely mounted, provide for adequate articulation at the connection without excessive slack, and be provided with a locking device that prevents accidental separation of the towed and towing vehicles.
• The rules applicable to devices used to couple vehicles together to pull trailers do not apply to devices used in driveaway-towaway operations.

The regulations governing the systems used to couple (connect) vehicles together are broken down into two sections: (1) vehicles using standard coupling devices to pull trailers (393.70) and “driveaway-towaway” vehicles, which involves piggy backing and tow-bar towing of other vehicles. (393.71)

Coupling devices and towing methods

The rules governing coupling devices and towing methods provide the requirements for vehicle tracking, fifth wheel assemblies, towing of full trailers, and safety devices in case of tow-bar failure or disconnection.

Tracking — The coupling devices connecting two or more vehicles operated in combination must be designed, constructed, and installed, and the vehicles must be designed and constructed, so that when the combination is operated in a straight line on a level, smooth, paved surface, the path of the towed vehicle will not deviate more than three inches to either side of the path of the vehicle that tows it.

Fifth wheel assemblies — The requirements for the mounting of the lower and upper half of fifth wheel assemblies, the locking of the assembly, and the location of the upper and lower half of the assembly are found in 393.70(b).

Towing full trailers — A full trailer must be equipped with a tow-bar and a means of attaching the tow-bar to the towing and towed vehicles. The tow-bar must:

• Be structurally adequate for the weight being drawn;
• Be properly and securely mounted;
• Provide for adequate articulation at the connection without excessive slack at that location; and
• Be provided with a locking device that prevents accidental separation of the towed and towing vehicles. The mounting of the trailer hitch (pintle hook or equivalent mechanism) on the towing vehicle must include reinforcement or bracing of the frame sufficient to produce strength and rigidity of the frame to prevent its undue distortion.

Safety devices — Every full trailer and every converter dolly used to convert a semitrailer to a full trailer must be coupled to the frame, or an extension of the frame, of the motor vehicle which tows it with one or more safety devices to prevent the towed vehicle from breaking loose in the event the tow-bar fails or becomes disconnected. (393.70(d))

Driveaway-towaway operations

The regulations governing coupling devices and towing methods for driveaway-towaway operations set forth the requirements for the maximum number of vehicles in combination, the carrying of vehicles on a towed or towing vehicle, the prohibition of bumper tow-bars on heavy vehicles, the restraint of the front wheels of a saddle-mounted vehicle, the towing of vehicles in a forward position, and several other important requirements. (393.71)

Tires

• Buses, trucks, and truck tractors must have a tread depth of at least 4/32 of an inch for its front (steering) tire and 2/32 of an inch for all other tires.
• A bus must not be operated with regrooved, recapped or retreaded tires on the front (steering) wheels, and trucks and truck tractors must not use regrooved tires with a load-carrying capacity equal to or over 4,920 pounds on its front wheels.
• Motor vehicles, except manufactured homes, must not be operated with tires that carry a weight greater than that marked on the sidewall of the tire or, in the absence of such a marking, a weight greater than that specified for the tires in any of the publications of any of the organizations listed in FMVSS No. 119.

General rules

The tire regulations state what tread depth is required for any bus, truck, or truck tractor (4/32 of an inch for a front (steering) tire and 2/32 of an inch for all other tires, when measured at any point in the tire’s major tread grooves). The regulations also provide that a motor vehicle cannot be operated on any tire that:

• Has body ply or belt material exposed through the tread or sidewall,
• Has any tread or sidewall separation,
• Is flat or has an audible leak, or
• Has a cut to the extent that the ply or belt material is exposed.
• Is speed-restricted and labeled with a maximum speed of 55 mph or less at speeds that exceed the rated limit of the tire.

In addition, a bus must not be operated with regrooved, recapped or retreaded tires on the front (steering) wheels, and trucks and truck tractors must not use regrooved tires with a load-carrying capacity equal to or over 4,920 pounds on its front wheels. (393.75(a)-(f))

Load restrictions

Motor vehicles, except manufactured homes (see 393.75(h)), must not be operated with tires that carry a weight greater than that marked on the sidewall of the tire or, in the absence of such a marking, a weight greater than that specified for the tires in any of the publications of any of the organizations listed in Federal Motor Vehicle Safety Standard (FMVSS) No. 119 (571.119, S5.1(b)). Exceptions to this weight rule exists for vehicles:

• Operated under the terms of a special permit issued by the state; and
• Operated at a reduced speed to compensate for loads in excess of the manufacturer’s rated capacity for the tire, but in no case may the reduced speed exceed 50 mph. (393.75(g))

Tire inflation pressure

Motor vehicles must not be operated on a tire that has a cold inflation pressure less than that specified for the load being carried. However, when the inflation pressure of the tire has been increased by heat because of the recent driving, the cold inflation pressure will be estimated by subtracting the inflation buildup factor from the measured inflation pressure (see 393.75(i), Table 1).

Plugged and patched tires

The use of plugged and patched tire is an area of confusion because there is no regulation delineating which tires can be patched or plugged or limiting how many times a tire can be patched or plugged. Tire manufacturers, carriers, and others, however, have recommended practices and policies that limit the use of patched or plugged tires. Therefore, many tire repair facilities will counsel a carrier to not use tires that have been plugged or patched on the steer axle (due to safety concerns related to possible future failure). Also, many carriers will not use a tire that has undergone any repair on the steer axle as a matter of policy. An exception to this exists in situations where a replacement tire cannot be purchased where the truck is located. In these situations, the vehicle may be operated on a repaired steer tire temporarily, until the vehicle can get to a location where a replacement tire can be installed.

Trailer rear bumper

• Trailers and semitrailers with a GVWR of 10,000 pounds or more, and manufactured on or after January 26, 1998, must be equipped with (or have installed) a rear impact guard that meets FMVSS requirements in effect at the time the vehicle was manufactured.
• Specific requirements govern the height, width, distance from the ground, surface area, certification, and labeling of rear impact guards.
• The rear impact guard requirements do not apply to pole trailers, pulpwood trailers, low chassis vehicles, special purpose vehicles, wheels back vehicles, and trailers towed in driveaway-towaway operations.

The rear end protection requirements (the rear bumper requirements) for trailers and semitrailers vary based on vehicle type and year of manufacture. The regulations state the required size and location of the bumper, and the associated National Highway Traffic Safety Administration (NHTSA) regulations (571.223 and 224), include the energy absorption and certification labeling requirements. (393.86).

Vehicles manufactured on or after January 26, 1998

Trailers and semitrailers with a gross vehicle weight rating (GVWR) of 10,000 pounds or more, and manufactured on or after January 26, 1998, must be equipped with a rear impact guard that meets the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 223 (571.223) in effect at the time the vehicle was manufactured. When the rear impact guard is installed on the trailer or semitrailer, the vehicle must, at a minimum, meet the requirements of FMVSS No. 224 (571.224) in effect at the time the vehicle was manufactured. (393.86(a))

The rear impact guard must also meet these requirements:

• Impact guard width — Must extend to within four inches of the side extremities of the vehicle, but not beyond the side extremity of the vehicle.
• Impact guard height — The vertical distance between the bottom edge of the guard and the ground must not exceed 22 inches.
• Guard rear surface — At any height 22 inches or more above the ground, the rearmost surface guard must be within 12 inches of the rear extremity of the vehicle. Theguard, however, may extend beyond the rear extremity of the vehicle.
• Cross-sectional vertical height — The horizontal member of each guard must have a cross sectional vertical height of at least 3.94 inches at any point across the guard width.
• Certification and labeling — Each rear impact guard must be permanently marked or labeled on the forward-facing or rearward-facing surface of the horizontal member of the guard, 12 inches in from the right end of the guard. The certification label must contain:
  • The impact guard manufacturer’s name and address,
  • The month and year that the guard was manufactured, and
  • The letters “DOT”, constituting a certification by the guard manufacturer that the guard conforms to all requirements of FMVSS No. 223.

Exceptions: These general rear impact guard requirements do not apply to pole trailers, pulpwood trailers, low chassis vehicles, special purpose vehicles, wheels back vehicles, road construction controlled horizontal discharge trailers, and trailers towed in driveaway-towaway operations. (393.86(a))

Vehicles manufactured after December 31, 1952

The regulations governing rear impact guards for motor vehicles manufactured after December 31, 1952 (except trailer or semitrailers manufactured on or after January 26, 1998) are found in 393.86(b).

Emergency equipment

• Each truck, truck tractor, or bus must be equipped with either: (1) a fire extinguisher having a UL rating of 5 B:C or more; or (2) two fire extinguishers, each of which has a UL rating of 4 B:C or more.
• Vehicles needing fuses to operate any required parts and accessories must have at least one spare fuse for each type or size of fuse needed for those parts and accessories.
• Vehicles, when stopped, must use as a warning device either three bidirectional emergency reflective triangles that conform to the requirements of the applicable FMVSS, or at least six fusees or three liquid-burning flares.

All trucks, truck tractors, and buses (except those towed in driveaway-towaway operations) must be equipped with fire extinguishers, spare fuses, and warning devices. (393.95)

Fire extinguishers

Each truck, truck tractor, or bus must be equipped with either (1) a fire extinguisher having an Underwriters’ Laboratories (UL) rating of 5 B:C or more; or (2) two fire extinguishers, each of which has a UL rating of 4 B:C or more. If the vehicle is used to transport hazardous materials in a quantity that requires placarding, it must be equipped with a fire extinguisher having a UL rating of 10 B:C or more.

Each fire extinguisher must:

• Be labeled or marked by the manufacturer with its UL rating.
• Be designed, constructed, and maintained to permit visual determination of whether it is fully charged.
• Be filled and located so that it is readily accessible.
• Be securely mounted to prevent sliding, rolling, or vertical movement relative to the motor vehicle.
• Use an extinguishing agent that does not need protection from freezing.
• Use extinguishing agents that comply with the toxicity provisions of the Environmental Protection Agency’s Significant New Alternatives Policy (SNAP) regulations. (393.95(a))

Spare fuses

Vehicles needing fuses to operate any required parts and accessories must have at least one spare fuse for each type or size of fuse needed for those parts and accessories. (393.95(b))

Warning devices

Vehicles must use one of the following warning devices when stopped:

• Three bidirectional emergency reflective triangles that conform to the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 125, 571.125; or
• At least six solid-fuel flares (fusees) or three liquid-burning flares, and as many additional fusees or flares as necessary.

Other warning devices may be used in addition to, but not in lieu of, the required warning devices. The additional warning devices must not decrease the effectiveness of the required warning devices. When red flags are used as warning devices, they must be at least 12 inches square, with standards adequate to maintain the flags in an upright position. (393.95(f), (k))

Note that at least one specific brand of battery-operated LED light has been approved for use as a warning device in place of the devices mentioned above.

Minimum burning requirements for flares

Each fusee must be capable of burning for 30 minutes, and each liquid-burning flare must contain enough fuel to burn continuously for at least 60 minutes. Fusees and liquid-burning flares must conform to the applicable UL requirements and be marked with the UL symbol. (393.95(h))

Hazardous material exception

Liquid-burning flares, fusees, oil lanterns, or any warning signal produced by a flame must not be carried on any:

• Commercial motor vehicle (CMV) transporting Division 1.1, 1.2, or 1.3 (explosives) hazardous materials;
• Cargo tank motor vehicle used for the transportation of Division 2.1 (flammable gas) or Class 3 (flammable liquid) hazardous materials whether loaded or empty; or
• CMV using compressed gas as a motor fuel. (393.95(g))

Structural components: Frames, cab and body components, and wheels

• The frame, chassis, bolts, or brackets securing the cab or body to the vehicle, must not be cracked, loose, sagging, missing or broken.
• No cab compartment door may be wired shut or otherwise secured in the closed position, unless the CMV is loaded with pipe or bar stock that blocks the door and the cab has a roof exit.
• Wheels and rims must not be cracked or broken, stud or bolt holes on the wheels must not be out of round, and nuts or bolts must not be missing or loose.

Vehicle frames, cabs and body components, and wheels are some of the parts and accessories necessary to the safe operation of a commercial motor vehicle (CMV). The specifications for these parts are described below.

Frames

The rules relating to CMV frames provide that:

• The frame or chassis must not be cracked, loose, sagging or broken.
• Bolts or brackets securing the cab or the body of the vehicle to the frame must not be loose, broken, or missing.
• The frame rail flanges between the axles must not be bent, cut, or notched, except as specified by the manufacturer.
• Parts and accessories must not be welded to the frame or chassis except in accordance with the vehicle manufacturer’s recommendations.
• Any welded repair of the frame must also be in accordance with the vehicle manufacturer’s recommendations.
• No holes may be drilled in the top or bottom rail flanges, except as specified by the manufacturer. (393.201)

Cab and body components

The cab compartment doors or door parts must not be missing or broken, the doors must not sag so that they cannot be properly opened or closed, and no door may be wired shut or otherwise secured in the closed position. An exception to the blocked door rule exists when a CMV is loaded with pipe or bar stock that blocks the door and the cab has a roof exit.

Other rules pertaining to the cab and body components provide that:

• Bolts or brackets securing the cab or the body of the vehicle to the frame must not be loose, broken, or missing.
• The hood must be securely fastened.
• All seats must be securely mounted.
• The front bumper must not be missing, loosely attached, or protruding. (393.203)

Wheels

Wheels and rims must not be cracked or broken, stud or bolt holes on the wheels must not be out of round, and nuts or bolts must not be missing or loose. (393.205)

Structural components: Suspension, steering wheel systems, and emissions

• The suspension system rules set forth specific requirements for axles, adjustable axle assemblies, leaf springs, coil springs, torsion bars, and the air suspension system’s regulator valve and exhaust controls.
• The steering wheel and steering column must be securely fastened, the amount of lash (play) in the steering wheel is limited, and the universal joints and ball-and-socket joints must not be worn, faulty, or repaired by welding.
• All components of the power steering system must be operable: no parts loose or broken; belts not frayed, cracked, or slipping; sufficient fluid in the reservoir; and no leaks in the system.

Some additional parts and accessories necessary to the safe operation of a commercial motor vehicle (CMV) include suspension, steering wheel, and power steering systems. The specifications for these systems are described below.

Suspension systems

The rules set forth for suspension systems include:

• All axles must be in proper alignment and no axle positioning part may be cracked, broken, loose, or missing.
• Adjustable axle assemblies must not have locking pins missing or disengaged.
• No leaf spring may be cracked, broken, missing, or shifted out of position.
• No coil spring may be cracked or broken.
• No torsion bar or suspension may be cracked or broken.
• The air suspension system’s air pressure regulator valve must not allow air into the suspension system until at least 55 pounds per square inch (psi) is in the braking system. The vehicle must be level, and air leakage must not be greater than 3 psi in a 5-minute period when the vehicle’s air pressure gauge shows normal operating pressure.
• The air suspension exhaust controls must not have the capability to exhaust air from the suspension system of one axle of a two-axle air suspension trailer unless the controls are either located on the trailer, or the power unit and trailer combination are not capable of traveling at a speed greater than 10 mph while the air is exhausted from the suspension system. This will not prohibit:
  • Devices that could exhaust air from both axle systems simultaneously; or
  • Lift axles on multi-axle units. (393.207)

Steering wheel systems

• The steering wheel must be secured and must not have any spokes cracked through or missing.
• The “play in the steering wheel” (steering wheel lash) must not exceed the parameters set forth in 393.209(b)(1).
  • For steering wheel diameters not listed in 393.209(b)(1), the steering wheel lash must not exceed 14 degrees angular rotation for manual steering systems, and 30 degrees angular rotation for power steering systems.
• The steering column must be securely fastened.
• Universal joints and ball-and-socket joints must not be worn, faulty or repaired by welding.
• The steering gear box must not have loose or missing mounting bolts or cracks in the gear box or mounting brackets.
• The pitman arm on the steering gear output shaft must not be loose.
• Steering wheels must turn freely through the limit of travel in both directions. (393.209)

Power steering systems

All components of the power steering system must be in operating condition, with no parts loose or broken. Belts must not be frayed, cracked, or slipping. The power steering system must have sufficient fluid in the reservoir, and system must not leak. (393.209(e))

Establishing a maintenance program

• Vehicles under an effective PM program are less likely to have an accident, are more productive and require less unscheduled repairs, and are more likely to pass roadside inspections.
• Careful PM recordkeeping provides invaluable information that can be used to refine maintenance schedules for individual vehicles and predict maintenance needs.
• PM is widely used, not only because it reflects a modern attitude of conservation (using assets wisely) but because it saves money.

Current regulations require that every motor carrier must systematically inspect, repair, and maintain, or cause to be systematically inspected, repaired, and maintained, all motor vehicles subject to its control. (396.3)

Fewer accidents

Regulations are not the only reason to run an effective preventive maintenance (PM) program. A well-maintained vehicle is less likely to be involved in an accident. A Federal Motor Carrier Safety Administration (FMCSA) study discovered that non-driver-related defects discovered during roadside inspections had a higher relationship to crashes. The study, done as part of the Compliance, Safety, Accountability (CSA) enforcement tool update, discovered that when a carrier’s on-road violations were sorted into driver-inspection related and non-driver-inspection related categories, the carriers that had a higher percentage of non-driver-related violations had a crash rate of 6.61. This is compared to 5.90 for carriers that had a higher rate of driver-inspection-related violations. The non-driver related defects are ones that are tied to components that drivers do not — or cannot — normally check during a pretrip inspection. In other words, these are defects that are directly tied to a fleet’s PM program.

Productivity enhanced

Also, vehicles that are under a PM program will be more productive and require less unscheduled maintenance and repair, which is more expensive than PM. To sum it up, PM leads to less accidents, better customer relations, and a lower cost of operation.

Roadside inspections

Another strong incentive for a good PM program is the possibility that the vehicle will be pulled over for a roadside vehicle inspection. If the vehicle is found to have a mechanical condition that might result in a breakdown or an accident, it will be put out of service. The vehicle cannot resume its trip until the unsafe condition is corrected.

Conservation

PM is also an attitude, a commitment. It doesn’t mean simply getting a vehicle into the shop and fixing what you see. It means being constantly on the lookout for things that might go wrong. It means getting the best, most cost-effective equipment for the vehicle and then taking care of it. This is much like preventive medicine that stresses good eating habits and regular exercise as a continuing prescription for good health and long life.

The PM philosophy is widely used, not only because it reflects a modern attitude of conservation, of using what assets one has wisely, but because it saves money. No one can argue with the bottom line. As PM takes hold, the standard of excellence for a maintenance shop changes from getting the fastest repairs to getting the fewest repairs.

Recordkeeping requirements

PM also requires careful recordkeeping of what is done. In addition to complying with regulations, PM records have another use. Once reliable PM schedules are established, they are refined for the individual vehicle and can be used to predict maintenance. Fleets that do not use records for more than simple documentation are not taking advantage of the goldmine of information that’s there. And it’s quite likely that those fleets are not managing their vehicles, the vehicles are controlling them.

To sum it up!

Vehicles that are put out of service or break down will require unscheduled maintenance (repairs). Repairs done on the road can be very costly both in lost productivity time and additional repair costs (commercial shops tend to have a considerably higher cost) when compared to the cost of operating a PM program. Using a “we’ll fix it when it breaks” maintenance program can get very expensive.

Determining maintenance intervals

• The three most common methods used for scheduling vehicles for PM are time, miles, and engine hours.
• Important sources of information for determining the actual interval used for PM include OEM recommendations; fleet repair records; input from drivers, technicians, and other shop personnel; and tracking of internal performance measures.
• In scheduling PM, it should be noted that emission system parts, such as diesel particulate filters, selective catalytic reduction systems, and exhaust gas recirculation components all require routine service.

Scheduling methods

The first decision that needs to be made when determining a preventive maintenance (PM) schedule is what method of measurement will be used. There are several methods used to schedule vehicles for PM. The three most common methods are:

• Time — This method is by far the easiest for management but is often the most wasteful as far as technicians’ time, parts, and cost. Scheduling vehicle preventive maintenance based on time means exactly what it says. A vehicle will be scheduled into the shop after a set number of days regardless of mileage or engine hours used since its last PM.
• Miles — Scheduling based on vehicle miles driven is the most common method used for scheduling vehicle PM. A vehicle will be scheduled into the shop after a pre-determined number of miles have been driven. The biggest problem with this method is that scheduling PMs based on mileage does not take into account issues such as severe duty, excessive engine idle time, and power take off (PTO) time (i.e., the transfer of mechanical power of the vehicle’s engine over to another piece of the equipment). To compensate for this, some carriers that schedule PM based on miles driven shorten the mileage interval to compensate for severe duty, excessive idling, or PTO time.
• Engine hours — Scheduling PMs based on engine hours makes sense for vehicles that work hard during every mile, but do not log many miles. Waste trucks, concrete haulers, and gravel trucks are all good examples of vehicles that are typically scheduled for PMs based on engine hours. The reason these trucks are routed into the shop for PMs based on engine hours is because they are constantly working hard — even though the truck may be averaging low miles per hour and miles per day.

The type of vehicles and the type of operation will determine the best type of PM scheduling for an individual company.

Important sources of information

The next step is determining the actual interval. Developing this part of the maintenance program will involve using information from several sources, including:

• The original equipment manufacturers’ (OEM) recommendations for the engine, transmission, and other components are the primary source and most important source of PM information. If the fleet has bought a new vehicle, it’s the only reliable source of information. The fleet should follow the recommendations exactly until its own experience proves otherwise. Fleets can also get information about expected component life from OEMs’ and plan accordingly. Fleets must be careful about deviating from the OEM’s recommendations. If a fleet deviates too far it may lose some, or all, of the warranty on the vehicle or vehicle components.
• Repair records (PM history) are the second source. Even if planning PM for a new vehicle, past maintenance history on similar vehicles that do the same work can provide important clues about how the fleet vehicles have been operating and will help plan the maintenance schedule for the new vehicle.
• Drivers, technicians, and other shop personnel are the third source. Ask these individuals for suggestions. A successful PM program will need the cooperation of everyone. These individuals should help to put the PM program together. Ask for specific ideas about the PM intervals.
• Tracking of internal performance measures can include oil sampling (if oil samples tested following oil changes are indicating oil breakdown, shortening the interval may be necessary), part failure analysis, unscheduled repairs, on-the-road repairs and breakdowns, and out-of-service violations. It does not make any difference how well a PM schedule matches up with the OEM’s recommendations if the vehicles are constantly breaking down or are constantly in need of major repairs (such as engine replacements).

Emissions systems

One issue that will need to be considered when establishing the maintenance interval is the need to service the emissions system. In vehicles built to the 2007 and 2010 emissions standards there are parts in the emissions system that require regular service. Diesel particulate filters (DPF), selective catalytic reduction (SCR) systems, and exhaust gas recirculation (EGR) components all require routine service.

Maintenance checklists

• PM checklists should be developed based on OEM recommendations, FMCSA regulations, vehicle maintenance history, and reports from company personnel.

Preventive maintenance (PM) involves scheduled inspection and maintenance of the vehicle. One key to making sure the necessary items are being inspected and maintained is the development of maintenance checklists. In developing a checklist, there are many factors that must be considered. Some of these factors are:

• OEM recommendations — All OEMs provide recommended inspection and maintenance items and procedures. These should serve as the basis for any program you develop.
• Regulations — Certain inspections are mandated in the Federal Motor Carrier Safety Administration (FMCSA) regulations. An example of a mandated inspection is the periodic (annual) inspection. The items found in Part 393 and Appendix A can serve as the basis for any checklist covering a required inspection.
• Maintenance history — By data-mining maintenance records and determining expected component life system (or cycle) (ECLS) and mean time between failures (MTBF) for various parts and components, it can be predicted when parts and components will become unreliable. Also, testing samples of fluids can determine the length of time fluids should be left in the various components, and therefore, the timing of fluid changes.
• Company personnel — If PM technicians are reporting that they are constantly having to repair a part or component on vehicles, and the part or component is not on the PM checklist, consideration should be given to adding it.

Other considerations

• Other important inspection and maintenance concepts include ECLS, MTBF, wear limits, and fluid sampling and testing.

When discussing inspection and maintenance, several concepts need to be explored, including:

• Expected component life cycle (ECLS)
• Mean time between failures (MTBF)
• Wear limits
• Fluid sampling and testing

Documenting preventive maintenance

• FMCSA regulations require that a company have a record system that documents the vehicle’s maintenance schedule, and the last and next scheduled service, including both the due date and the nature of the service.
• To set up and document a PM program, the maintenance manager should divide vehicles into “dynamic groups” based on similar traits and maintenance requirements, write a PM schedule for each group, place the schedule in the corresponding vehicle files, keep track of each scheduled PM, and record when the next scheduled PM is due.

The Federal Motor Carrier Safety Administration (FMCSA) regulations require that a company have a record system that shows the vehicle’s maintenance schedule, and the last and next scheduled service (both due date and nature of the service).

The regulations do not spell out how a company is to accomplish this; nor do they provide a “required schedule” or “required form and format” for documentation. The regulations only require that a company have a systematic maintenance program and document it. One reason the FMCSA does not “spell out” a preventive maintenance (PM) schedule that carriers must follow is because of the wide variety of commercial vehicles that are in operation and covered by the regulations. Everything from pickup trucks to motorcoaches to tractor-trailers are covered by the regulations.

Steps by the maintenance manager

To develop and document a PM program, a maintenance manager will need to develop and document the maintenance program for each vehicle (or group of vehicles). This is not as complicated as it sounds.

• First, for PM purposes, and later tracking, the maintenance manager should divide the vehicles in the fleet into “dynamic groups.” Each group should be made up of similar vehicles (based on similar traits and maintenance requirements, not necessarily make and model).
• Next, review the existing information for each group and write a PM schedule (including intervals, checklists, and wears points for important and high-wear components).
• After the schedule for each of the dynamic groups has been established, copy the schedule and place it into the corresponding vehicle files. As well as containing the PM information, the vehicle files must also contain identifying information (vehicle number, make, VIN, year, tire size, and the entity providing the vehicle if it is not owned by the company), and records of all inspections, maintenance, and repairs. This is required by the FMCSA regulations under 396.3.
• Finally, either on a form in the file or physically on the file, keep track of each scheduled PM, and record when the next scheduled maintenance is due.

Some companies go one step further to make the process easier. In addition to the files, they use a wall board that displays the individual vehicles and last/next service. This way, technicians and supervisors can tell immediately when a vehicle received scheduled PM last, and if it is coming due for its next service.

Driver Training: Driving Habits and PM

• Drivers must believe that taking care of a vehicle is important and that it can extend vehicle and component life, contribute to vehicle safety, and save money for the fleet.
• Drivers can make a tangible contribution to PM through good driving habits and the maintenance manager may be asked to assist in driver training to achieve a fleet’s cost-cutting goals.

The driver’s commitment to preventive maintenance (PM) begins where the inspection report leaves off. The driver must inspect for safety, but it has also been seen how important accurate, consistent driver observations can be in alerting mechanics to potential problems. Here’s where attitude comes in. The driver must believe that taking care of the vehicle is important and that it can really extend vehicle and component life, contribute to a safe vehicle, and save money for the fleet.

Drivers make an even more tangible contribution to PM through personal driving habits. If the fleet has developed specific cost-cutting maintenance policies, it is fleet management’s responsibility to train drivers to accomplish these goals. The maintenance manager may be asked to assist in that training in an effort to reduce maintenance costs, extend equipment life, and promote fuel economy, all areas directly affected by driving habits. Four subjects can be used as examples: tires, brakes, clutch, and fuel economy.

Driver’s Role in Maintenance

• Drivers perform a pretrip inspection to determine if a vehicle is in safe operating condition and a post-trip inspection (called a DVIR) to determine if there is a defect in the vehicle that needs to be addressed by maintenance.
• Mechanics and drivers can work together as partners to ensure that the fleet stays in excellent condition.

Pre- and post-trip inspections

A driver is required to perform a pre-trip inspection (392.7 and 396.13) to determine that the vehicle is in safe operating condition. If the vehicle is not in safe condition, the driver cannot operate it until it has been repaired. The driver is also required to complete a written post-trip inspection report on vehicle condition at the completion of each day’s work (called a driver vehicle inspection report, or DVIR), if there is a defect on the vehicle (see 396.11). This report is then submitted to the carrier for action. Some carriers require drivers to submit a DVIR after each workday, even if there is no defect to report.

The driver is primarily concerned with reporting safety problems; each time the driver operates the vehicle, the driver’s pretrip inspection certifies that the vehicle is in safe condition.

Driver inspections vs. PM inspections

Driver inspections are different than preventive maintenance (PM) inspections. PM inspections are performed by maintenance personnel and involve in-depth inspection of vehicle components, possibly requiring the removal of access covers and other components to conduct the inspection, and involve specific measurements of parts and components.

Drivers and mechanics as partners in maintenance

The maintenance team approach sees the driver as a partner in maintenance. When the driver goes a step beyond the specific driver inspection report, looking and listening for potential problems that may be developing and reporting them to the maintenance department, the driver is contributing to the PM program. Problems unrelated to safety are reported so that the vehicle can be checked during the next scheduled maintenance inspection. Body damage, a hose starting to show wear, etc. are important clues that need further investigation and attention.

To sum it up, driver inspections are concerned with what condition the vehicle is presently in, while a PM is concerned with keeping the vehicle in good condition. By working as partners and allowing responsibilities to overlap, the mechanics and drivers can keep the fleet in excellent condition.

Maintenance case study

• Even though the automatic slack adjusters repeatedly required readjusting, the actual brake components were not checked and there was no investigation of the underlying cause, i.e., why the automatic slack adjusters required repeated readjusting.
• Readjusting the automatic slack adjusters was only a “temporary fix,” according to the brake manufacturer’s materials, and the underlying cause of the out-of-adjustment situation needed to be investigated and corrected.

What follows is a case study on how vehicle maintenance scheduling and practices (including recordkeeping and training) can all be combined to create a dangerous (in this case a fatal) situation.

Facts

The National Traffic Safety Board (NTSB) investigated a crash involving an air brake equipped dump truck that was unable to stop while descending a grade in Glen Rock, PA, striking four vehicles that were stopped at an intersection at the bottom of the grade. One of the four other vehicles also struck three pedestrians after being hit by the dump truck.

The brake failure was so complete that even after striking the vehicles the dump truck continued through a gas station, over a set of railroad tracks, coming to rest 300 feet past the intersection. The truck at this point was 407 feet from where it had first impacted another vehicle.

As a result of the accident the driver, owner, and a manager from the company involved were convicted of various criminal violations involving negligence.

The rear brakes on the dump truck were “Type 30” (30 square inches of diaphragm area) and the steer axle was equipped with “Type 16” brakes (16 square inches of diaphragm area). All brake units were equipped with automatic slack adjusters.

Results of the investigation

The post-accident investigation determined that the larger rear brakes had not provided any braking force due to being severely out of adjustment. Because the larger rear brakes were not providing any brake force the smaller front brakes were trying to slow the vehicle and load (the vehicle was found to be overweight at the time of the accident). These brakes quickly overheated during the downhill braking. As a result of the overheating the front brakes “faded” and failed. At this point the vehicle had no braking power.

Discussion

The fact that the rear brakes were out of adjustment was the cause of the accident, therefore the automatic slack adjusters caused the accident, right?

Wrong! The brake units from the vehicle were tested by the NTSB after the accident. During the testing it was discovered that the clevises and pins that attached the brake chamber push rod to the slack adjuster were so badly worn that the automatic slack adjusters could not achieve correct adjustment. As part of the testing the clevises and pins were replaced, and the automatic slack adjusters immediately brought the units into adjustment.

In short, the automatic slack adjusters had not failed. The other brake components on the truck were in such poor condition that the automatic slack adjusters could not function correctly.

The NTSB investigated the truck further and discovered that the truck had the automatic slack adjusters manually readjusted multiple times. The driver that had driven the truck the previous summer had been placed out of service due to the brakes being out of adjustment. To clear the out-of-service violation he manually readjusted the automatic slack adjusters. During that summer the driver stated he had manually readjusted the automatic slack adjusters “at least three or four more times.”

In January, during an annual inspection, the brakes were found to be out of adjustment again. At that time, the mechanic performing the inspection readjusted the automatic slack adjusters.

In April, three days before the Glen Rock accident the truck had rolled into a car. According to the driver the brakes had not “held.” It is not known if the brakes were readjusted after the incident (there is no documentation of a repair).

To sum it up, the automatic slack adjusters on the truck had been adjusted at least five times, and possibly many more times in the previous 12 months. Due to the incomplete records, it is not known exactly how many times the brakes had been adjusted. Also, the company did not include brake components (other than checking adjustment) in their preventive maintenance.

Here is the key point!

No one checked the actual brake components or investigated why the automatic slack adjusters required readjusting. The manufacturer’s material warns that readjusting the automatic slack adjusters is only intended to be a “temporary fix.” The underlying cause must be corrected, or the out-of-adjustment situation will return.

Periodic, or annual inspections

• An annual inspection requirement applies to all CMVs owned by a carrier, but also requires a carrier to ensure that those vehicles controlled by and operated by the carrier have been inspected annually.
• Annual or periodic inspections by the carrier must be performed a qualified inspector and, if inspections are performed by an outside shop, the carrier must make sure the inspections are completed and done according to the regulations.
• The qualified inspector performing annual inspections must prepare a report for each inspection which identifies the name of the individual performing the inspection, the motor carrier operating the vehicle, the date of the inspection, the vehicle inspected, and the components inspected.

The Federal Motor Carrier Safety Regulations (FMCSRs) require commercial motor vehicles (CMVs) be inspected at least once every 12 months. (396.17, 396.19). The vehicle must meet the requirements established in Appendix A to the regulations to pass the inspection. If a component does not meet the standards, it must be repaired before the vehicle can pass the inspection and resume operation. This is known as the “periodic” or “annual” vehicle inspection requirement.

This requirement also applies to intermodal equipment providers. Intermodal freighting consists of the transport of products and raw materials in a closed container by a variety of vehicles, such as ships, trains, and semi-trailer trucks. Intermodal equipment providers are required to see to it that any intermodal equipment provided to motor carriers (primarily intermodal chassis) have been annually inspected.

The regulations require that all CMVs controlled by a carrier and operated in interstate commerce pass an inspection at least annually. This means that carriers are not only responsible for the annual inspection of vehicles they own but must ensure that vehicles provided by others, such as intermodal equipment providers and leasing companies, have been annually inspected.

Periodic inspections must be performed by a qualified inspector who meets the requirements found in 396.19.

Outside inspections

If a carrier has an outside shop perform some or all of its periodic inspections, it must make sure that the shop is actually doing the inspections, and that the inspections are being done in accordance with the regulations. The carrier is still responsible for the inspection, even if it is done by another party.

There are cases (both criminal and civil) involving maintenance managers being held responsible for poor periodic inspections done by outside shops. The civil cases have involved maintenance managers not verifying that the outside shop was doing the periodic inspection correctly. The criminal cases involved maintenance managers knowing that the outside shops were not doing the inspections correctly. In one criminal case that led to jail time, the maintenance manager knew the shop was not even conducting the inspections, even though the carrier was receiving the required reports and decals (the vehicles were never in the outside shop that issued the reports and decals).

Documentation of periodic inspections

Section 396.21 provides the documentation rules for periodic inspections. The qualified inspector performing annual inspections must prepare a report for each inspection which identifies:

• The name of the individual performing the inspection
• The motor carrier operating the vehicle
• The date of the inspection
• The vehicle inspected
• The components inspected

All periodic inspection reports must be retained where the vehicles are housed or maintained for 14 months.

Proof on the vehicle

A copy of the inspection report, or a decal containing minimal information about the inspection, must be on the inspected vehicles. If a decal is used,it must include:

• The inspection date,
• The name and address of the location where the inspection report is being kept,
• Information identifying the vehicle if the vehicle is not clearly marked, and
• A certification that the vehicle passed an inspection in accordance with 396.17.

The regulations do not specify where the inspection sticker has to be placed on the vehicle. However, the driver is responsible for making sure an inspector can access the sticker upon request, so the driver has to know where the sticker is located and has to make sure that it remains legible and current.

New vehicles must also carry proof of annual inspection, but a vehicle dealer who complies with the inspection requirements may provide the documentation (sticker and/or inspection report) for the initial inspection.

The North American Out-of-Service Criteria (OOSC)

• Generally, if a vehicle has an Appendix A defect that would cause it to fail a periodic inspection, it may be placed out of service during a roadside inspection.
• A vehicle with an Appendix A defect that would lead to not passing a periodic inspection may still be allowed to continue under OOSC and repaired later in the day or before its next trip, rather than placing it out of service.

The areas listed in Appendix A are also the basis for the North American Out-of-Service Criteria (OOSC), published by the Commercial Vehicle Safety Alliance (CVSA) with a few differences. Generally, if the vehicle has a defect that would cause it to not pass a periodic inspection, it may be placed out of service during a roadside inspection conducted under 396.9.

Out-of-service orders

Any vehicle placed out of service must be repaired before it can resume operating on the roadway. This will require having the vehicle repaired at the location of the inspection, or having the vehicle towed to a repair facility. Documentation of the repairs (and towing if the vehicle was towed) will need to be handled and filed correctly to verify that the terms of the out-of-service order were complied with.

Differences between Appendix A and OOSC

Generally, the OOSC follows Appendix A. The distinction between the two is that when there are differences, the OOSC is not as strict as Appendix A. An example would be brakes. One defective brake (bad shoe, drum, or brake out-of-adjustment) would lead to a vehicle not passing a periodic inspection because of the Appendix A requirements. In the OOSC, the vehicle may be allowed to continue if only one brake has a defect. The vehicle is still in violation and the vehicle would not pass a periodic inspection, but the inspector may allow it to continue its trip and be repaired later in the day or before it is operated again after the driver’s workday, rather than placing it out of service.

Relationship between Appendix A and OOSC

It is important to understand the relationship between the regulations, Appendix A, and the OOSC. The regulations in Part 393 and Appendix A provide the condition the vehicle must be always in when it is operating on the roadway. Any defect that is a violation of the regulations in Part 393 or that is listed in Appendix A can be noted as a violation on a roadside inspection. The violation will then be used in the scoring in the Compliance, Safety, Accountability (CSA) program. Also, the carrier and/or driver can be warned or cited (fined) for any violation of Part 393.

If the inspector finds a defect that is a violation of Part 393, the next question is, “Does the defect warrant an out-of-service order?” To determine if the defect warrants an out-of-service order, the inspector will compare the defect to the OOSC. If the defect is specifically mentioned in the OOSC, and the condition matches the criteria provided, the vehicle may be placed out of service.

The legal actions taken because of a violation (the warning or citation) and the decision to place the vehicle out of service are not necessarily related. A vehicle found to have defective headlights during daylight hours can be warned or cited for having defective required lights because a non-working headlight is a violation of the regulations. However, it will generally not be placed out of service as it is not a safety-critical issue at the time of the inspection.

To sum up!

The OOSC is strictly intended to get vehicles that are in an unsafe condition repaired before allowing them to continue.

Exceptions: Braking rules

• Exceptions to the general rule that all wheels on a CMV must be equipped with brakes are provided for certain older trucks/tractors with three or more axles, motor vehicles being towed in a driveaway-towaway operation, semitrailers or pole trailers, full trailers or four-wheel pole trailers, the steering axle of a three-axle dolly which is steered by a co-driver, loaded house moving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and similar motor vehicles.
• Exceptions to the general rule that all wheels equipped with brakes must be operative are provided for certain towed vehicles with disabling damage, vehicles being towed in a driveaway-towaway operation, unladen converter dollies, the steering axle of a three-axle dolly which is steered by a co-driver, raised lift axles, loaded house moving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and similar motor vehicles.
• Exceptions to the general rule that all wheels equipped with brakes must be operative are provided for devices designed to reduce the front wheel braking effort and surge brakes.

Overview

There are several exceptions to the rules that (1) all commercial motor vehicles (CMVs) must be equipped with brakes acting on all wheels, and (2) all brakes with which a motor vehicle is equipped must always be capable of operating.

There are also braking exceptions for devices designed to reduce the front wheel braking effort and for surge brakes.

Exception: Brakes acting on all wheels

These exceptions, found in 393.42(b), include:

• Trucks or truck tractors having three or more axles and manufactured before July 25, 1980, are not required to have brakes on the front wheels. These vehicles must meet the brake performance requirements in 393.52
• Motor vehicles being towed in a driveaway-towaway operation (including the last truck of triple saddle-mount combinations) are not required to have operative brakes provided the combination of vehicles comply with the brake performance requirements in 393.52.
• Any semitrailer or pole trailer (laden or unladen) with a gross weight of 3,000 pounds or less is not required to be equipped with brakes if the axle weight of the towed vehicle does not exceed 40 percent of the sum of the axle weights of the towing vehicle.
• Any full trailer or four-wheel pole trailer (laden or unladen) with a gross weight of 3,000 pounds or less is not required to be equipped with brakes if the sum of the axle weights of the towed vehicle does not exceed 40 percent of the sum of the axle weights of the towing vehicle.
• Brakes are not required on the steering axle of a three-axle dolly which is steered by a co-driver.
• Loaded house moving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and similar motor vehicles are not required to be equipped with brakes, provided certain speed and braking requirements for the combination of vehicles are met.

Exception: Brakes always operative

The requirement, in 393.48(a), that all brakes with which a motor vehicle is equipped must always be capable of operating does not apply to:

• A towed vehicle with disabling damage.
• A vehicle which is towed in a driveaway-towaway operation and is included in the exemption to the requirement in 393.42(b) for brakes on all wheels.
• Unladen converter dollies with a gross weight of 3,000 pounds or less and manufactured prior to March 1, 1998.
• The steering axle of a three-axle dolly which is steered by a co-driver.
• Loaded house moving dollies, specialized trailers and dollies used to transport industrial furnaces, reactors, and similar motor vehicles provided certain speed and braking requirements for the combination of vehicles are met.
• Raised lift axles. Note: Brakes on lift axles must be capable of being applied whenever the lift axle is lowered and the tires contact the roadway.

Devices to reduce or remove front-wheel braking effort — A CMV may be equipped with a device to reduce the front wheel braking effort (or in the case of a three-axle truck or truck tractor manufactured before March 1, 1975, a device to remove the front-wheel braking effort) if that device meets the applicable requirements for manually operated (393.48(b)(1)) and automatic (393.48(b)(2)) devices.

Surge brakes — Surge brakes, designed to slow or stop a towed vehicle, are excepted from the requirement that all brakes be operative at all times as set forth in 393.48(d).

Automatic brake adjusters and indicators

• New CMVs equipped with hydraulic, or air brakes systems must meet the automatic brake adjustment systems requirements of the FMVSS applicable to the vehicle at the time of manufacture.
• For new CMVs equipped with an air brake system containing an external automatic adjustment mechanism and an exposed pushrod, the condition of service brake under-adjustment must be displayed by a brake adjustment indicator conforming to the requirements of the FMVSS applicable to the vehicle at the time it was manufactured.

Hydraulic brake systems and air brake systems on new commercial motor vehicles (CMVs) must be equipped with automatic brake adjusters (“slack adjusters”) that automatically adjust as the brake linings and drums wear. Air brake systems must also be equipped with a brake system indicator that shows the condition of the service brake under adjustment. If the CMV was built with automatic slack adjusters, they cannot be removed and replaced with manual slack adjusters (see 393.53).

Adjustment systems:

• Hydraulic brakes systems — Each CMV manufactured on or after October 20, 1993, and equipped with a hydraulic brake system, must meet the automatic brake adjustment system requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 105 (49 CFR 571.105, S5.1) applicable to the vehicle at the time it was manufactured.
• Air brake systems — Each CMV manufactured on or after October 20, 1994, and equipped with an air brake system must meet the automatic brake adjustment system requirements of FMVSS No. 121 (49 CFR 571.121, S5.1.8 or S5.2.2) applicable to the vehicle at the time it was manufactured.

Brake adjustment indicator:

• Air brake systems — On each CMV manufactured on or after October 20, 1994, and equipped with an air brake system which contains an external automatic adjustment mechanism and an exposed pushrod, the condition of service brake under-adjustment must be displayed by a brake adjustment indicator conforming to the requirements of FMVSS No. 121 (49 CFR 571.121, S5.1.8 or S5.2.2) applicable to the vehicle at the time it was manufactured.

Antilock brake system (ABS)

• Each truck and bus manufactured on or after March 1, 1999, with a hydraulic brake system, must have both an ABS and ABS malfunction indicator system that meets federal standards.
• Each air braked truck tractor manufactured on or after March 1, 1997, and each CMV other than a truck tractor (i.e. trucks, buses, semitrailers, converter dollies, and full trailers), manufactured on or after March 1, 1998, must have an ABS that meets federal requirements.
• Certain vehicles with air brake systems must be equipped with an electrical circuit that sends a signal warning in the event of an ABS malfunction.

In March 1995, the National Highway Traffic Safety Administration (NHTSA) issued rules requiring antilock brake systems (ABS) for heavy trucks, tractors, trailers, and buses. Since the Federal Motor Carrier Safety Administration (FMCSA) has adopted these regulations in 393.55, all commercial motor vehicles (CMVs) built with ABS must have working ABS. These ABS rules provide specific requirements for:

• Hydraulic brake systems
  • ABS malfunction indicators for hydraulic braked vehicles
• Air brake systems
  • ABS malfunction circuits and signals for air braked vehicles
• Exterior ABS malfunction indicator lamps for trailers

The ABS rules in 393.55 do not apply to vehicles engaged in driveaway-towaway operations.

Hydraulic brake systems

Each truck and bus manufactured on or after March 1, 1999, with a hydraulic brake system, must have an ABS meeting the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 105 (571.105, S5.5).

ABS malfunction indicators — Each hydraulic braked vehicle manufactured on or after March 1, 1999, must have an ABS malfunction indicator system that meets the requirements of FMVSS No. 105 ( 571.105, S5.3).

Air brake systems

Truck tractors — Each air braked truck tractor manufactured on or after March 1, 1997, must have an ABS meeting the requirements of FMVSS No. 121 (571.121, S5.1.6.1(b)).

CMVs (other than truck tractors) — Each air braked CMV other than a truck tractor, manufactured on or after March 1, 1998, must have an ABS that meets the requirements of FMVSS No. 121 (571.121, S5.1.6.1(a) for trucks and buses, and S5.2.3 for semitrailers, converter dollies and full trailers).

ABS malfunction circuits and signals — Certain vehicles with air brake systems must be equipped with an electrical circuit that sends a signal warning in the event of an ABS malfunction:

• Each truck tractor manufactured on or after March 1, 1997, and each single-unit air braked vehicle manufactured on or after March 1, 1998, must have an electrical circuit that will signal a malfunction that affects the generation or transmission of response or control signals to the vehicle’s ABS. (571.121, S5.1.6.2(a))
• Each truck tractor manufactured on or after March 1, 2001, and each single-unit vehicle that is equipped to tow another air-braked vehicle, must have an electrical circuit that will transmit a malfunction signal from the ABS on the towed vehicle(s) to the trailer ABS malfunction lamp in the cab of the towing vehicle, and must connect the electrical circuit to the towed vehicle. (FMVSS No. 121, 571.121, S5.1.6.2(b))
• Each semitrailer, trailer converter dolly, and full trailer manufactured on or after March 1, 2001, must have an electrical circuit that will signal a malfunction in the trailer’s ABS and must have the means for connection of the ABS malfunction circuit to the towing vehicle. In addition, each trailer manufactured on or after March 1, 2001, that is designed to tow another air-brake equipped trailer must be able to transmits a malfunction signal from the ABS of the trailer(s) it tows to the vehicle in front of the trailer. (FMVSS No. 121, 571.121, S5.2.3.2)

Exterior ABS malfunction indicator lamps for trailers — Each air braked trailer (including a trailer converter dolly) manufactured on or after March 1, 1998, must have an ABS malfunction indicator lamp which meets the requirements of FMVSS No. 121 (571.121, S5.2.3.3).

Emergency exits on buses

• Each bus manufactured on or after September 1, 1994, must meet the applicable federal emergency exit requirements in effect on the date of manufacture.
• Each bus, including a school bus used in interstate commerce for non-school bus operations, must meet applicable federal requirements in effect on the date of manufacture.
• Each bus and each school bus used in interstate commerce for non-school bus operations, manufactured on or after September 1, 1973, must meet the applicable federal emergency exit identification and operating instruction requirements in effect on the date of manufacture.

Emergency exit rules for buses, found in 393.62, vary based on when the bus was manufactured.

• If manufactured on or after September 1, 1994:
  • Each bus with a gross vehicle weight rating (GVWR) of 10,000 pounds or less must meet the emergency exit requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 217 (S5.2.2.3) in effect on the date of manufacture
  • Each bus with a GVWR of more than 10,000 pounds must have emergency exits which meet the applicable emergency exit requirements of FMVSS No. 217 (S5.2.2 or S5.2.3) in effect on the date of manufacture.
• If manufactured on or after September 1, 1973, but before September 1, 1994:
  • Each bus (including a school bus used in interstate commerce for non-school bus operations) with a GVWR of more than 10,000 pounds must meet the requirements of FMVSS No. 217, S5.2.2 in effect on the date of manufacture.
  • Each bus (including a school bus used in interstate commerce for non-school bus operations) with a GVWR of 10,000 pounds or less must meet the requirements of FMVSS No. 217, S5.2.2.3 in effect on the date of manufacture
• The regulations also set forth the emergency exit requirements (393.62(c)) and laminated safety glass/push-out window requirements (393.62(d)) for buses manufactured before September 1, 1973.

“Emergency Exit” markings and instructions

Each bus and each school bus used in interstate commerce for non-school bus operations, manufactured on or after September 1, 1973, must meet the applicable emergency exit identification or marking requirements of FMVSS No. 217, S5.5, in effect on the date of manufacture. The emergency exits and doors on all buses must be marked “Emergency Exit” or “Emergency Door” followed by concise operating instructions, located within six inches of the release mechanism, describing each motion necessary to unlatch or open the exit. (393.62(e))

Prisoner exception

The emergency exit requirements do not apply to buses used exclusively for the transportation of prisoners. (393.62(f))

Emissions

The emissions standards, found in the EPA regulations at 40 CFR Part 86, are normally addressed by the vehicle manufacturers. Where they make a difference to carriers is that they increase the cost of equipment and the emissions systems must be maintained, adding to maintenance costs. However, the vehicle must be able to meet the emissions standard that was in place at the time the engine was manufactured. If the vehicle is not properly maintained, it is only a matter of time until it can no longer meet the relevant standards. Also, if the fuel, air, or emissions system is tampered with or improperly modified, the vehicle will no longer meet the applicable standards. This can lead to significant fines in the states that do roadside testing of emissions.

If the vehicle operates in California, there is also a chance that the emissions system may need to be upgraded (retrofitted with an improved emissions system). This is due to California placing stricter emissions standard on older vehicles than the standards that were in place when older engines were manufactured. To accomplish this, California is phasing in the new requirements over time. The long-term goal in California is to have all diesel powered vehicles operating in California equipped with engines that meet at least the 2010 emission standards by 2023.

The national emission standards are issued by the Environmental Protection Agency (EPA). As a maintenance manager, it will be your responsibility to make sure the vehicles continue to comply with the standards that cover the vehicle. There are two key compliance areas you need to be concerned with: the emissions standards and the emissions label requirements.

The emission standards are issued based on the date of engine manufacture. As an example: If the date of manufacture was before 2004, the engine would have to meet the 1998 standards that were in place at the time of manufacture. The vehicle can be upgraded to a later standard (there are several EPA programs that provide grants or loans for just such a purpose); however, it cannot be allowed to fall below the standards that were in effect on the date of manufacture.

To meet these standards, OEMs had to create new technology and emission components (covered below), because simply improving engine electronics and combustion technology could not meet the new standards. To sum it up, after-treatment of the exhaust has become necessary as of the 2007 standards.

Also, meeting these standards (in particular the new PM standard) required the development of “clean fuels.” This is also covered below.

It is a violation of federal law to tamper with or remove any emissions components. Removing, disabling, or deliberately allowing any part of the emissions control system to become inoperative (including modifying the emission control software in the engine control module) is a violation of Section 203(a)(3) of the Clean Air Act, and can lead to a significant fine from the Environmental Protection Agency.

Two cases show the risks involved in altering the emissions systems on vehicles. The first involves a small carrier that was caught removing the emissions control components required on model year 2010 and newer vehicles. This carrier was fined $50,000. The second case involved a repair facility that was caught altering the emissions systems on customers’ vehicles by reprogramming the engine control modules (ECMs). This repair facility was fined $75,000.

The vehicle is also subject to inspection and testing to verify that it is complying with the emission standards that were in effect at the time of manufacture. This can be done at the roadside by state officers or as part of a state-based inspection program. If the vehicle has been altered or cannot pass an emissions test due to alteration or lack of proper maintenance, the company can be fined by the state.

Diesel particulate filters

To meet the allowable particulate discharge requirements, manufacturers of heavy-duty vehicles had to develop new technology. One of these new technologies is the diesel particulate filter, or DPF.The concept of a DPF is not new (they have been around since the 1980s). With the emissions standard changes in 2004 and 2007, OEMs had to adapt the technology to on-road heavy diesels.

One point about DPFs — they are not directly required. What is required is that the particulate discharge be below the regulatory thresholds. To meet these requirements, most OEMs have decided to install DPFs. If the DPF is needed to meet the standard, it is required to be on the vehicle.

The principle of a DPF is similar to most filters. The DPF cleans exhaust gas by forcing the gas to flow through the filter which “scrubs out” the particulates. The DPF then oxidizes the trapped particulates, converting them into less harmful components. There are a variety of diesel particulate filter technologies on the market. Several DPFs use a filter material that is also a catalyst that helps reduce other emissions (carbon monoxide and hydrocarbon byproducts).

There are several types of DPFs. Most use a ceramic wallflow honeycomb filter design. This type of filter uses cordierite (a ceramic material that is also used as catalytic converter cores) as the filter medium to trap particulates. These filters also have a honeycomb design to attempt to provide more air flow areas than a standard filter.

Any DPF will be subject to soot and ash build-up. This is normally taken care of through “passive regeneration.” This occurs when the exhaust flow temperature becomes high enough to oxidize the built up particulates. Some systems use “active regeneration,” which increases the exhaust temperature to increase regeneration and improve exhaust flow. All active regeneration systems use extra fuel, whether through burning to heat the DPF, or providing extra power to the DPF’s electrical system.

Exhaust gas recirculation

Exhaust gas recirculation (EGR) is a NOx emissions reduction technique used in many diesel engines to meet emission standards.

EGR works by recirculating a portion of an engine’s exhaust gas back to the engine cylinders, intermixing the incoming air with recirculated exhaust gas dilutes the mix with inert gas, lowering the flame temperature, and (in diesel engines) reducing the amount of excess oxygen. The exhaust gas also increases the specific heat capacity of the mix, lowering the peak combustion temperature.

Because NOx formation progresses much faster at high temperatures, EGR serves to limit the generation of NOx. NOx is primarily formed when a mix of nitrogen and oxygen is subjected to high temperatures. By keeping temperatures lower, the generation of NOx is reduced.

There are some drawbacks to EGR. Adding EGR to a diesel engine reduces the specific heat ratio of the combustion gases in the power stroke. This reduces the amount of power that can be extracted by the piston and can increase the amount of particulate in the exhaust. If the engine uses EGR, there may be additional capacity requirements pertaining to the DPF.

Another consideration with EGR systems is how they get the exhaust gas into the engine. Modern systems utilizing electronic engine control computers, multiple control inputs, variable geometry turbochargers, and servo-driven EGR valves to accomplish this. These systems will require additional maintenance and must be considered when developing PM schedules.

Selective catalytic reduction

Selective catalytic reduction (SCR) is a means of converting nitrogen oxides (NOx), an unwanted emission from a diesel engine, with the aid of a catalyst into diatomic nitrogen (an inert gas) and water.

To accomplish this, a gaseous reducing agent (urea in the case of on-road diesel engines) is added to the exhaust flow in a materially- and geometrically-controlled environment. The ensuing chemical reaction causes the conversion of NOx into nitrogen and water, which are then discharged out of the SCR unit with the exhaust flow.

SCR systems do come with some problems, the primary one being the additional maintenance requirements. If the unit is allowed to run out of urea, it will not function. When this happens, the engine control module will automatically reduce engine power until the SCR system is fully functional again. Also, it is another area of the exhaust system that will see additional heat.

Much like the DPF, the SCR unit needs to be removed from the vehicle and cleaned or replaced as part of PM. As with the DPF, there is no magic number as to when this must be done, due to the variables within each operation and the differing conditions that the vehicles and engines can be in.

Another problem is if the SCR system fails, it could create additional back-pressure on the exhaust, leading to a loss in performance and additional heat problems.

All major engine manufacturers in the medium and heavy-duty engine market have gone to SCR to meet the 2010 emission requirements. Most use a combination approach, combining SCR with engine performance adjustments (electronic control adjustments, and air and fuel flow adjustments) and/or EGR to achieve the required NOx levels. One original equipment manufacturer attempted to meet the requirements on their engines through the use of EGR-only technology (some of their 2010 to 2012 engines did not have SCR). However, all manufacturers are now using SCR to meet the requirements.

The reducing agent that the manufacturers have settled on for on-road diesel engines is urea. As a result, vehicles built with SCR-equipped engines need to be spec’ed with a “diesel exhaust fluid,” or “DEF” (urea) tank. The size and serviceability of the tank needs to match the carrier operation unless the carrier is willing to purchase DEF on the road at retail prices. Example: An over-the-road vehicle will need a larger DEF tank than one involved in local delivery that receives weekly maintenance. The other consideration is the additional weight that a large DEF tank (when full) will add to the vehicle. Maintenance managers need to consider the following in relation to the SCR-equipped vehicles:

• Vehicle specifications involving the DEF tank and SCR unit.
• Inventory levels for SCR replacement parts.
• Inventory levels for DEF.
• Technician training on the DEF systems and SCR units.
• Inspection procedures for the DEF/SCR system.
• Preventive maintenance items relating to the DEF system and SCR unit.
• Replacement intervals or replacement decision points for SCR units.
• Driver training pertaining to inspecting, filling, and troubleshooting the DEF and SCR systems on the road.
  • An initial decision in this area will need to be made. Do you intend to allow drivers to do anything other than inspect the system?

Clean fuels

Ultra-low sulfur diesel (ULSD) is the diesel fuel currently in use for on-road engines. It has substantially lower sulfur content when compared to older fuels. Older diesel fuel formulas contained roughly 500 parts per million (ppm) of sulfur. ULSD contains less than 15 ppm of sulfur. As of 2006, diesel fuel and kerosene pumps were required to be labeled with EPA-authorized language disclosing fuel type and sulfur content.

While sulfur is not a lubricant, the process used to refine ULSD reduces the lubricating properties of the fuel. The lubricating characteristics of the fuel lubricates and protects the various parts of the engine’s fuel injection system from wear. To manage this change, ASTM International (formerly the American Society for Testing and Materials) adopted the lubricity specification defined in ASTM D975 for all diesel fuels, and this standard went into effect January 1, 2005. Engine oil manufacturers also adjusted their products to compensate for the changes in the fuel formulation created by the refining process of ULSD.

CARB

CARB (California Air Resources Board or simply ARB inside California) is a unique, non-political agency in California that was created to move air-quality decision out of the political process. CARB regulates everything from power plant emissions to windshield washer fluid. Basically, anything entering the air in California is under their authority.

CARB has several programs that have an impact on the transportation industry. Some of these programs only apply to California-based equipment, while others apply to any diesel-powered vehicle operating in California (regardless of where it is registered). This section of the manual includes a listing of the CARB requirements that apply to all vehicles operating in the State of California. Vehicles registered in California have additional requirements, such as periodic smoke inspection requirements.

While CARB and some of the CARB programs are unique to California and California-based vehicles, many other states have similar rules. It is important that a maintenance manager be familiar with any emissions requirements (such as periodic emissions testing) that are in effect in the state where the vehicles are based.

Drayage Trucks emissions

This program applies to all trucks that haul into, out of, or within port and rail facilities in California. This regulation requires the registration of all trucks entering and operating in ports and rail facilities, and establishes emissions reduction requirements that began phasing in as of January 1, 2010 (vehicles can be registered at www.arb.ca.gov/drayagetruck). As of January 1, 2010, class 8 trucks equipped with pre-1994 engines were no longer allowed into the facilities. As of the most recent phase-in, class 7 and 8 trucks equipped with model year 1994 to 2006 engines must meet the 2007 emissions standards (as of January 1, 2014). This involves replacing the engine in the older trucks with a newer engine (2007 or newer) or replacing the truck with a 2007 or newer truck. The final step is all trucks operating in the port and rail facilities meeting the 2010 engine emission standards by January 1, 2023 (2010 and newer engines are fully compliant and will not require any updating).

Emission control label inspection program

This involves all vehicles operating in California. If the vehicle engine is missing its emission control labeling, the owner can be fined.

Heavy-Duty Diesel Vehicle Inspection Program (HDVIP) and Periodic Smoke Inspection Program (PSIP)

Under the Heavy-Duty Diesel Vehicle Inspection Program (HDVIP), any heavy-duty diesel vehicle operating in California can be inspected at any time to make sure it is meeting the emissions standards in place the year the engine was manufactured. Part of the inspection also includes verifying that the required emission control system components are present and have not been tampered with. Many states have similar roadside emission inspection programs.Heavy-duty diesel vehicles registered in California are also subject to periodic (regularly scheduled) emissions inspections under the periodic smoke inspection program (PSIP). This is another emission program that many other states also have in place for vehicles registered in their states.Under the PSIP program, all diesel-power vehicles with a GVWR of greater than 6,000 pounds must have a smoke opacity test once the engine is four years old. The test must be conducted by a CARB-trained individual. Records of all tests must be retained for two years. Fleets that conduct thier own testing are required to maintain records of personnel training, and testing and repair records for each vehicle tested for a minimum of two years.

Idling Reduction Program

Idling of any heavy-duty vehicle is limited to no more than five minutes in California. Also, any heavy-duty vehicle operated in California with a MY 2008 or newer engine must have an automatic “shut-down” that turns the engine off after five minutes of idling. There are a few exceptions to this rule (Clean Idle vehicles, operating auxiliary equipment, loading and unloading passengers, etc.). However, idling to control cab temperature while the driver is resting in a sleeper berth is not one of the exceptions (this is one of the common misconceptions).

TRUs

CARB has rules in place that began phasing in as of December 2008 pertaining to Transport Refrigeration Units (TRUs). TRUs are defined as a refrigeration system (a system designed to heat or cool products) that is powered by a diesel engine that is used in the transportation of goods. This definition includes the standard refrigerated units (the diesel engine directly powers the compressor) and generator set (genset) refrigeration units that use a diesel engine to run a generator to provide power to an electric refrigeration unit. Refrigeration systems that do not use a diesel engine for power (are powered off a power unit’s main engine or are powered by “shore power”) are not considered to be TRUs by these regulations.

These rules require covered TRUs to meet the ultra low emission TRU (ULETRU) emissions standards. These limit emissions to 0.02 g/hr-hp if the diesel engine produces over 25 hp, or to be equipped with an emission system meeting the Level 3 VDECS retrofit standards.

Here is a breakdown of the specific compliance dates:

• As of August 1, 2009: All owners and operators of California-based TRUs must file with CARB and secure an Air Resource Board Identification Number (ARB IN) by completing an application (for each TRU) that includes owner information, TRU information (year, make, model, identification number, etc.), engine information (year, make, model, horsepower, identification number), compliance status with the performance standards, and how compliance was achieved. Once CARB has assigned the TRU an ARB IN, the company has 30 days to display the number on the TRU. This is the only requirement that out-of-state TRUs do not have to meet (voluntary compliance is allowed for out-of-state TRU owners and operators).
• All TRUs that cannot meet the ULETRU standards must have be retrofitted to meet the ULETRU standards.

If you cannot justify bringing an older TRU into compliance, you do have the option of removing the TRU from service and using the vehicle for the transportation of dry goods. However, the TRU must be completely disabled in such a manner that the engine cannot operate (removal of the engine, removal of a significant portion of the engine, removal of the refrigeration unit from the TRU, etc.). Also, whatever is done to disable the unit must be visually verifiable.

Regulation to reduce emissions from in-use on-road diesel vehicles, a.k.a. the “Truck and Bus” rule

In 2008, CARB passed rules requiring that all diesel-powered trucks and buses with a weight rating of 14,000 pounds or more be brought up to the 2010 diesel particulate matter (DPM or simply PM) and Nitrogen Oxide (NOx) emissions requirements. This will be accomplished by requiring all vehicles built before 2010 to undergo a retrofit. This rule is informally called the Truck and Bus rule. Much like the TRU rules, the retrofit requirements and schedule will be based on the MY of the vehicle’s engine. The implementation began by requiring vehicles with engines from MY 1996 to 1999 be retrofitted to meet the PM requirements by January 1, 2012, and ends when all covered vehicles with pre-2010 engines are retrofitted to meet the 2010 standards by January 1, 2023. Here is the implementation schedule:

Where are we at today? As of January 1, 2021, heavy trucks and buses that were originally equipped with a 2004 or older MY engine must have been retrofitted with a 2010 engine, and heavy trucks and buses with a MY 2005 to 2006 engine must be equipped with an approved PM filter to be operating legally in California. Also, as of January 1, 2020, the California Department of Motor Vehicles (DMV) will no longer issues vehicle registrations to vehicles that are not in compliance with these requirements. Part of the registration process for a California-based vehicle covered by these requirements is verifying the vehicle meets the appropriate emissions retrofitting requirements.As of January 1, 2022, vehicles with engines from MY 2005 and 2006 will have to be retrofitted with an engine meeting the MY 2010 emissions standards to operate in California.There is a separate implementation schedule for lighter trucks and buses (with a GVWR of 14,000 to 26,000 pounds). As of January 1, 2021, all covered vehicle with a MY 2006 or older engine must be retrofitted with an engine meeting the 2010 standards. As of January 1, 2023, all covered vehicles with an engine older than MY 2010 must be retrofitted with an engine meeting the 2010 standards.Exceptions to the truck and bus rule include the following:

• “Low-mileage” vehicles (a vehicle that operates fewer than 1,000 miles in California) may operate in California without being retrofitted. Carriers are required to register the vehicle with CARB and enter its odometer reading during January of each year.
• Vehicles operating exclusively in certain areas in California may operate without having been retrofitted with an engine meeting the 2010 requirements. The vehicles must remain entirely in these specified areas and meet the DPF requirements.
• A one-time, three-day temporary permit available for carriers that do not normally operate older vehicles in California.

To use any of the exceptions and to be able to register the older California-based vehicles covered by the retrofitting requirements, the company has to register using the TRUCRS online registration tool before the applicable deadline. This is where CA DMV will be looking to determine if a covered vehicle meets the applicable standards and therefore is entitled to a new registration.Details can be found at the CARB website at https://ww2.arb.ca.gov/our-work/programs/truck-and-bus-regulation.

Regulation to reduce greenhouse gas emissions

This CARB regulation currently requires new and existing 50-foot or longer box-type trailers and the tractors pulling them (there are no requirements related to buses in this regulation) to be equipped with aerodynamic technologies and low-rolling resistance tires when operating on California highways. For purposes of the regulation, a box-type trailer is a dry-van trailer or a refrigerated-van trailer. The regulation does not apply to tractors pulling other types of trailers, e.g., box-type trailers of lengths shorter than 50 feet, flatbeds, logging trailers, drop-frame trailers, curtain-side trailers, and chassis trailers hauling shipping containers. Also exempt from the requirements of the regulation are authorized emergency vehicles and military tactical support vehicles, as well as drayage tractors that operate exclusively within a 100 mile radius. There are exceptions available through CARB for short-haul and local tractors and trailers, and the movement of storage trailers.

Beginning January 1, 2010, a 2011 and subsequent model year tractor with a sleeper berth that pulls a 50-foot or longer box-type trailer on a California highway is required to be a U.S. EPA-certified SmartWay tractor. SmartWay does not currently certify a tractor without a sleeper berth; i.e., day cab, and thus, these tractors would not be required to be SmartWay certified. As of MY 2014, all tractors are built to meet the federal greenhouse gas standards, so 2014 and newer trucks do not need to be Smartway Certified.

In addition, low-rolling resistance tires that meet U.S. EPA SmartWay specifications are required on all tractors that pull a 50-foot or longer box-type trailer on a California highway.

Trailers subject to the regulation must be either SmartWay certified or retrofitted with SmartWay verified technologies, including low rolling resistance tires and aerodynamic technologies. Meeting the aerodynamic requirements involves installing side skirts and front and/or rear fairing to achieve a demonstrated 5 percent improvement in fuel mileage. Refrigerated trailers that require retrofitting are required to use aerodynamic that have demonstrated a 4 percent improvement in fuel mileage. What kinds of equipment will meet the requirements of this regulation? To comply with the regulation, you may purchase a SmartWay certified or greenhouse gas reduction compliant tractor and/or trailer, which will come equipped with the approved technologies. You may also comply by retrofitting your trailer with approved low rolling resistance tires and one or more of the following aerodynamic technologies:

• Trailer rear fairings
• Trailer front gap fairings
• Trailer side skirts
• Other SmartWay approved technologies

The type or number of technologies required will be based on the percentage of greenhouse gas emissions reduction of each device. These required percentages can be found in the regulation at: www.arb.ca.gov/regact/2008/ghghdv08/ghghdv08.htm.

As of January 1, 2022, this program was to have moved into Phase 2. This will bring more trailers into the requirements, including box-type trailers under 50 feet, flatbeds, and tankers. The trailer standards can be met through aerodynamic improvements, low rolling resistance tires, tire pressure systems (Tire Pressure Monitoring System/Automatic Tire Inflation System), and/or weight reduction, depending on the type of trailer. However, at least initially, the changes will be limited to new trailers. Manufacturers will have to certify that the trailer meets the standards in the regulations, and the carrier will be required to maintain the trailer as built.

Currently, the move to Phase 2 has been delayed due to a stay in the related federal standards, the current abeyance in the D.C. Circuit litigation related to the related federal standards invovled, the delay in reconsideration by the federal agencies, and the uncertainty concerning the characterization of trailers as new motor vehicles under the Clean Air Act. CARB has stated they will provide the industry with six months notice before implementing and enforcing these regulations.

As a best practice, many carriers have chosen to voluntarily adopt the use of SmartWay and CARB-equipped tractors, trailers, and tires, even though they do not operate in California or the trailer involved in not required to meet the standards. This is due to the improved fuel mileage, and therefore lower operating costs, seen by vehicles meeting these standards.

On-board diagnostics

On September 8, 2008, the U.S. EPA granted the CARB waiver request related to on-board emissions diagnostics. Under this CARB rule, all heavy-duty vehicles operating in California built in MY 2010 or later must have an on-board diagnostic system that notifies the driver if the emissions system is not functioning correctly. The diagnostic system must monitor all vehicle systems and components that can effect emissions, such as fuel, catalytic converter, turbocharger, exhaust gas recirculation, particulate matter filter, cooling, and valve timing.

If a malfunction is detected by the system, the diagnostic system must immediately report the malfunction to the driver (via a dash display). The rule requires that the driver be notified as soon as any component involved in the emissions system malfunctions, not when the emissions exceed the regulatory limits. This regulation matches an existing regulations pertaining to light-duty vehicles.

There was initial objection to this rule in the OEM and transportation industries, based on having to design and install such a system to satisfy one state. However, that argument was put to rest when the U.S. EPA enacted a regulation similar to the CARB rule. Under the U.S. EPA rule heavy-duty engine manufacturers must begin building engines that have an emissions diagnostic system starting in MY 2010, and all heavy-duty diesel engines built from MY 2013 on must be equipped with a diagnostic system.