Many workplaces service large vehicle wheels, such as those found on trucks and buses. These operations require trained service personnel as well as physical safeguards to protect against parts flying off the wheel and other hazards. Servicing tires on rim wheels, both multipiece and single-piece, can result in a wheel being propelled great distances, causing serious injury or death to anyone in the trajectory.

The Occupational Safety and Health Administration (OSHA) provides the 29 CFR 1910.177 —Servicing multipiece and single-piece rim wheels standard that applies only to servicing multipiece and single-piece rim wheels used on large vehicles such as trucks, tractors, trailers, buses, and off-road machines. It does not apply to servicing rim wheels on automobiles, or on pickup trucks and vans utilizing automobile tires or truck tires designated “LT.”

• Defining and explaining terms associated with wheel and rim servicing can increase understanding of the process and contribute to its safety.

Terms associated with wheel and rim servicing are defined in the following list of definitions. These terms include:

Barrier: A fence, wall, or other structure or object placed between a single-piece rim wheel and a service worker during tire inflation, to contain the rim wheel components should air contained in the single-piece rim wheel suddenly be released.

Charts: The U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA) publications entitled Demounting and Mounting Procedures for Tube-Type Truck and Bus Tires, Demounting and Mounting Procedures for Tubeless Truck and Bus Tires, and Multipiece Rim Matching Chart. OSHA also will accept any other manual or poster that provides at least the same instructions, safety precautions, and other information contained in these publications, which is applicable to the types of wheels the employer is servicing.

Demounting: The opposite of mounting.

Installing: The transfer and attachment of an assembled rim wheel onto a vehicle axle hub.

Mounting: The assembly or putting together of wheel and tire components to form a rim wheel, including inflation.

Multipiece rim wheel: The assemblage of a multipiece wheel with the tire tube and other components.

Multipiece wheel: A vehicle wheel consisting of two or more parts, one of which is a side or locking ring designed to hold the tire on the wheel by interlocking components when the tire is inflated.

Removing: The opposite of installing.

Restraining device: An apparatus such as a cage, rack, assemblage of bars, and other components that will constrain all rim wheel components during an explosive separation of a multipiece rim wheel, or during the sudden release of air contained in a single-piece rim wheel.

Rim manual: A publication containing instructions from the manufacturer or other qualified organization for correct mounting, demounting, maintenance, and safety precautions pertaining to the type of wheel being serviced.

Rim wheel: An assemblage of tire, tube, liner (where appropriate), and wheel components.

Service area: That part of an employer’s premises used for servicing rim wheels, or any other place where rim wheel service occurs.

Service or servicing: The mounting and demounting of rim wheels and related activities such as inflating, deflating, installing, removing, and handling.

Single-piece rim wheel: The assemblage of a single-piece rim wheel with the tire and other components.

Single-piece wheel: A vehicle wheel consisting of one part, designed to hold the tire on the wheel when the tire is inflated.

Trajectory: Any potential path or route that a rim wheel component may travel during an explosive separation, or the sudden release of pressurized air, or an area in which an air blast from a single-piece rim wheel may be released. The trajectory may deviate from paths that are perpendicular to the assembled position of the rim wheel at the time of separation or explosion. (See Appendix A for examples of trajectories.)

Wheel: The portion of a rim wheel that provides the method of attachment of the assembly to the axle of a vehicle and also provides the means to contain the inflated portion of the assembly (i.e., the tire and/or tube).

• Information in training programs for wheel servicing must be presented in a way that all employees can understand.
• Employers have multiple responsibilities to ensure that their facilities and their workers are prepared for wheel servicing.

All general industry employers are required to have a training program in place for wheel servicing. This program should include information about hazards and safety procedures for employees who service rim wheels. The program should also include sharing the information on Occupational Safety and Health Administration (OSHA) wheel charts, rim manuals, and its 29 CFR 1910.177 regulations covered in this checklist. Note: Charts are required to be posted in the lab or shop.

If employees cannot read or understand the charts or rim manuals, the information must be conveyed in a manner they can comprehend. Employees who service rim wheels must demonstrate that they can work on these wheels safely. They should be able to demonstrate acceptable performance if they can:

• Understand and use OSHA’s charts,
• Deflate and demount tires,
• Identify rim wheel components and inspect for defects,
• Inflate tires with a restraining device/safeguard,
• Mount tires safely,
• Use the restraining device or barrier and other equipment required by OSHA,
• Inflate a tire on a single-piece rim wheel mounted on a vehicle,
• Safely handle rim wheels, and
• Remove and install rims.

An imperative part of the training is that employees understand the trajectory should the tire fail when being inflated and when the wheel is inspected following inflation. They should know where to stand to be outside of that trajectory.

Employees who service rim wheels must be individually evaluated on their ability to perform these tasks and service rim wheels safely. If anyone is not proficient in servicing rim wheels, that worker must be provided additional training and be re-evaluated. Employers are required to only allow successfully trained employees to service rim wheels.

Employers must prepare both their facilities and employees for wheel servicing operations. They should:

• Only allow trained individuals to service large wheels.
• Make the required tire charts available to workers.
• Furnish a restraining device for inflating tires on multipiece wheels. Also, they should provide a restraining device or barrier for inflating tires on single-piece wheels unless the rim wheel will be bolted onto a vehicle during inflation.
• Assure that an air-line assembly consisting of the following components be used for inflating tires: (1) a clip-on chuck; (2) an in-line valve with a pressure gauge or a pre-settable regulator; and (3) a sufficient length of hose between the clip-on chuck and the in-line valve (if one is used) to allow the service worker to stand outside of the trajectory.
• Furnish and assure that only tools recommended in the rim manual for the type of wheel being serviced are used to service rim wheels.
• Ensure that multipiece wheel components are not to be interchanged except as provided in the charts or the applicable rim manual.
• Inspect multipiece wheel components and single-piece wheels prior to assembly.
• Establish a safe operating procedure for servicing wheels and assure that employees are instructed in and follow that procedure. See 1910.177(f) and (g) for specific required procedures.
• Ensure that employees use the tools recommended in the rim manual for the type of rim being serviced and have the current charts and/or rim manuals available for use during service.

• Restraining devices and barriers must undergo inspection before each day of use and after any rim wheel component separation or sudden release of air.
• Interchanging of wheel components is forbidden except as specified in the charts or appropriate manual.

Employers are required to ensure the correct tire-servicing equipment is available and usable. This includes ensuring safety devices such as restraints are suitable for the task and employees are checking for wheel component compatibility.

Restraining devices

Restraining devices or barriers are required to have 150% maximum tire specification pressure capacity to withstand the maximum force that would be transferred to it during a rim wheel separation. To protect employees, the restraining devices and barriers need to be capable of preventing the rim wheel component from being thrown outside or beyond the device or barrier. These devices and barriers are to be furnished for inflating tires on multipiece and single-piece wheels.

The restraining devices and barriers must be inspected before each day’s use and after any separation of the rim wheel component or sudden release of contained air. This inspection should include checking for:

• Cracked or broken components or welds;
• Bent or sprung components caused by mishandling, abuse, tire explosion, or rim wheel separation;
• Pitting/corrosion of components; and
• Any structural damage that would decrease effectiveness.

If any damage is found during the inspection or use of equipment, the equipment is to be immediately removed from service. It can only be returned to service after it has been checked by the manufacturer or a registered professional engineer.

The air-line assembly used for inflating tires has a clip-on chuck, an in-line valve with a pressure gauge or preset table regulator, and a sufficient length of hose between the clip-on chuck and in-line valve (if one is used) to enable the worker to stand outside of the trajectory.

Wheel component acceptability

Wheel component acceptability is important to maintain a safe wheel. Interchanging components is strictly prohibited, except as permitted in the charts or the applicable rim manual.

All multipiece wheel components and single-piece wheels must be inspected before assembly and use. Rim flanges, rim gutters, rings, bead seating surfaces, and bead areas of tires should be clear of any dirt, surface rust, scale, or loose or flaked rubber buildup before mounting and inflation as these contaminants can cause improper inflation and create a hazard for employees. The components should be checked for compatibility before installation. This would include the size of the tires and wheels as well at the type of tires and wheels.