Excavation and trenching - New York

New York operates an OSHA-approved State Plan covering only state and local government workers. Private sector employers and their workers are covered by federal OSHA.

The New York Public Employee Safety and Health (PESH) Bureau is part of the New York Department of Labor. New York PESH has generally adopted all OSHA standards applicable to state and local government employment.

Underground facilities

Every operator of an underground facility must participate in a one-call notification system which receives notices of intent to excavate from excavators. The system notifies operators of proposed excavations, and the operators are then required to locate and mark their underground facilities to prevent damage, interruption of service, or injury to excavation workers. The rules governing the notification system are found at NY CLS Gen Bus §§ 760 – 767.

Excavation operations

Stability of structures. Except in hard rock, whenever any excavation is to be performed in the vicinity of buildings, structures or utilities, the integrity, stability and structural adequacy of such buildings, structures or utilities must be maintained at all times by the use of underpinning, sheet piling, bracing or other equivalent means to prevent damage to or failure of foundations, walls, supports or utility facilities and to prevent injury to any person. Underpinning, sheet piling, bracing or equivalent means must be inspected at least once each day or more often if conditions warrant. Every such inspection shall be conducted by an experienced, designated person.

Prohibited entry. No person must be required or permitted to enter any trench or similar excavation where they may be exposed to side or bank failure or cave-in unless proper safeguards for their protection have been provided.

Trench and area type excavations

Sheeting and shoring. Whenever any person is required to work in or is lawfully frequenting any trench or excavation five feet or more in depth which has sides or banks with slopes steeper than those permitted in Table I of 12 NYCRR § 23-4.2, such sides or banks must be provided with compliant sheeting and shoring. Such sheeting and shoring system must be in contact with the sides or banks of such trench or excavation.

Inspections and additional protection. A designated person must carefully inspect such sheeting and shoring at least once each day and more frequently in the event of rain, the presence of additional surface or ground water from any source, excessive ground vibrations or whenever additional loads of any kind have been imposed near or adjacent to such excavation. Additional protection against slides and cave-ins shall be provided whenever necessary.

Side or bank protection. Any trench or excavation in clay, sand, silt, loam or nonhomogeneous soil which has sides or banks more than three feet but less than five feet in depth must be provided with compliant side or bank protection. Such side or bank protection will not be required where an employer maintains on file at the excavation site a dated certification in writing by a designated person who is qualified by training and experience indicating that such person has examined the sides and banks and has found them to be stable and not subject to failure or cave-in.

Sloping of excavation sides or banks. Where the sides or banks of a trench or area type excavation may be sloped back without causing subsidence or damage to buildings, structures, utilities, roads, streets, highways or similar facilities, sloping of the excavation sides or banks may be used as protection in lieu of sheeting and shoring, provided such sloping conforms to the values set forth in Table I of 12 NYCRR § 23-4.2. Such sloping of the excavation sides or banks may be used in combination with sheeting and shoring. When such a combination is used, a level bench at least 24 inches in width must be left between the toe of the sloped section and the braced section. The sheeting of the braced section must extend at least 12 inches above the elevation of such level bench.

Below ground water. Any unbraced sloped excavation which extends below the ground water table, especially adjacent to rivers, reservoirs or other bodies or sources of free water, must be under the direct supervision of an experienced person designated by the employer.

Combination support. In any excavation with a combination of sloped unbraced sides or banks near the surface and vertical sheeted and shored sides or banks near the bottom, the steepest allowable slope of such unbraced portion of the sides or banks must be based on the total excavation depth.

Undercuts and reverse sloping. Where any side or bank of an excavation is undercut and has a reverse slope toward the trench centerline creating a vertical load on the sheeting and shoring, such sheeting and shoring must be designed by, and installed in accordance with the specifications determined by, a professional engineer licensed to practice in the State of New York. Such sheeting and shoring must be designed to support the vertical load imposed by the overhanging material as well as the load imposed by the adjacent ground.

Falling material. Excavated material and other superimposed loads must be placed at least 24 inches back from the edges of any open excavation and placed or piled so that no part thereof can slide, fall or roll into the excavation. Such 24-inch required clearance may be reduced if the employer installs a barrier or similar retaining device which is designed and constructed to prevent excavated material from falling into the excavation.

Adjacent areas. All sides or banks, slopes and areas in and adjacent to any excavation must be stripped and cleared of loose rock or any other material which may slide, fall, roll or be pushed upon any person located in such excavation.

Guarding of open excavations. Any open excavation adjacent to a sidewalk, street, highway or other area lawfully frequented by any person must be effectively guarded. Such guarding must consist of:

• A substantial fence or barricade; or, in the alternative;
• An extension of the sheeting above the ground surface adjacent to the excavation to a height of at least 42 inches above the adjacent street, highway or other area lawfully frequented by any person.

Protection in lieu of guarding. In lieu of such guarding, protection may be afforded by a substantial covering installed over such excavation. The covering must consist of planking at least two inches thick full size, properly supported exterior grade plywood at least three-quarters inch thick or material of equivalent strength.

Where it is possible that the movement of vehicles or other heavy equipment will take place over such covering, the covering must be of sufficient strength to withstand such loading without structural failure of the covering or of the support system.

Guarding of unattended open excavation. Where no work is being performed in an unattended open excavation which has substantially vertical sides or banks three feet or more in depth, the excavation must be effectively guarded on all open sides regardless of the location. Such guarding must consist of:

• A fence, barricade, or safety railing; or as an alternative;
• An extension of the sheeting above the excavation to a height of at least 42 inches above the adjacent ground, grade or equivalent level.

Instead of guarding, protection may be afforded by a substantial covering installed over the excavation. The covering must consist of planking at least two inches thick full size, properly supported exterior grade plywood at least three-quarters inch thick or material of equivalent strength.

Where it is possible that the movement of vehicles or other heavy equipment will take place over such covering, the covering must be of sufficient strength to withstand loading without structural failure of the covering or of the support system.

Structural walls. Temporary sheet piling installed in an excavation to permit the construction of a retaining or structural wall must be left in place until the wall has developed adequate strength to support any load intended to be imposed upon such wall.

Dislodged material or falling equipment. Persons must not be required or permitted to work in any area where they may be struck or endangered by any excavation equipment or by any material being dislodged by or falling from such equipment.

Stable rock. The sides of any excavation in stable rock may be vertical and are not required to be provided with sheeting and shoring. The sides must be scaled and kept free of all loose rock or material that may be dislodged or may fall into the excavation.

Access to excavations

Ladders, stairways or ramps constructed must be provided in every excavation more than three feet in depth for safe access and egress. Such ladders, stairways or ramps must be installed in sufficient number and in such locations as to be readily accessible to any person wishing to enter or leave such excavation without more than 25 feet of lateral travel.

Sheeting, shoring, and bracing

Where any excavation is not protected by sloped sides or banks in compliance with Table I of 12 NYCRR § 23-4.2, any person in such excavation must be protected by sheeting, shoring and bracing in compliance with Tables II, III and IV of 12 NYCRR § 23-4.

Shores, struts, and brace requirements. Shores, struts and braces, whether horizontal or inclined, must be of adequate size to provide stiffness and adequately braced to withstand the loads imposed upon them. The ends of all braces must be individually anchored and fastened to fully resist all imposed forces and to prevent such braces from shifting or slipping. The placing of any inclined shores, struts or braces at any angle exceeding 30 degrees from the horizontal is prohibited.

Earth-supported. Each earth-supported shore, strut or brace must bear against a footing of sufficient area and stability to prevent any subsidence, yield or shifting of such shore, strut or brace.

Stringers. The end of each stringer must be individually braced. Where stringers are terminated to form individual panel type sheeting, each panel must be braced at either end.

Self-supporting movable shields. In lieu of sheeting and shoring and where conditions permit, a self-supporting movable shield of timber or metal may be used and moved ahead as the excavation and construction progresses. The supporting capacity of a shield must be equal in all respects to the sheeting and shoring set forth in Tables II, III and IV of 12 NYCRR § 23-4. When any person is in an excavation at any point not protected by such shield, sheeting and shoring as set forth in Tables II, III and IV of 12 NYCRR § 23-4 must be provided.

Screw jacks. In lieu of wood, screw jacks of adequate size and stability may be used as cross bracing in the sheeting and shoring of any excavation. Any type of cross bracing used must be in a true horizontal position, securely fastened and prevented from shifting or slipping by adequately fastened scabs or blocks.

When two vertical lengths of sheeting are required. When the depth of an excavation requires the use of two vertical lengths of sheeting, one above the other, the lower sheeting must be set inside the bottom stringers of the upper sheeting and be driven down and braced as the excavation continues.

Parallel to underground utilities. Excavations which are generally parallel to existing underground pipelines, utilities or structures of any kind must be tightly sheeted and shored alongside such pipelines, utilities or structures where they are exposed by such excavations.

Timber sheeting requirements. Timber sheeting must consist of structurally sound hardwood at least two inches by six inches in size or of lumber of equivalent strength. The actual thickness of timber sheeting must be consistent with the size of the supporting timbers and the depth of the excavation.

Excavating machines

Footing. Excavating machines must not be used where unstable conditions or slopes of the ground or grade may cause such machines to tilt dangerously. To prevent such unstable conditions, mats of timber or equivalent means to afford stable footings must be provided.

Protection of operators. Where an operator of an excavating machine may be exposed to an overhead hazard, the equipment must be provided with a cab or equivalent cover affording protection against such hazard.

Operation. Excavating machines must be operated only by designated persons. In addition:

• No person except the operating crew may be permitted on an excavating machine while it is in motion or operation.
• No person other than the pitman and excavating crew may be permitted to stand within range of the back of a power shovel or within range of the swing of the dipper bucket while the shovel is in operation.
• When an excavating machine is not in use, the blade or dipper bucket must rest on the ground or grade.
• The operator of an excavating machine must not leave the controls of such machine at any time when the master clutch is engaged, and the engine is operating.
• Oiling and greasing must be performed only while an excavating machine is at rest and the master clutch disengaged.
• The boom or the bucket, dipper or clamshell of a power shovel must not pass over the seat or cab of a truck or other vehicle while any person is in such seat or cab.
• The operation of excavating machines near power lines or power facilities must comply with 12 NYCRR Part 23.
• Material must not be pushed manually into the path of trenching machines.
• The operator of any excavating machine must not leave the controls of such machine until he has lowered the bucket or blade into firm contact with the ground or grade surface.
• Every mobile power-operated excavating machine except for crawler mounted equipment must be provided with an approved warning device that automatically sounds a warning signal audible to all persons in the vicinity of the machine above the general noise in the area when such machine is backing.

Underground utility work within state highway right-of-way

Standards. Underground work must be in accordance with the nationally recognized standards. Regional Offices may impose more stringent conditions in a permit based upon prevalent weather and traffic conditions.

Installations. Pavement crossings for underground utilities must be accomplished by jacking, driving, drilling, boring, or tunneling. The edge of the excavation (nearest to the pavement) used for driving or jacking must not be less than 10 feet, measured laterally from the curb, or edge of shoulder at shoulder break, whichever provides more clearance. When the highway configuration or other circumstances preclude the minimum offset, the Department of Transportation may consider approving an alternate configuration and offset.

Temporary pavement repairs. Temporary pavement repairs with cold patch or other acceptable bituminous patching must be made as soon as backfilling is done. It must be maintained flush with the pavement surface until the backfill has been properly compacted, and permanent restoration of the pavement surface is completed.

Sheeting. Where excavation is within the pavement area or when the depth of excavation is greater than the distance from the edge of pavement to the edge of trench, sheeting may be required.

Backfill. Backfill material must be of a quality and type acceptable to the Department and must be compacted sufficiently to preclude future settlement of the excavated area. The backfill material must be of a quality so as not to block or intercept the drainage of the subgrade. Excavations for service connections must be backfilled within two days.

• Within roadway. Within the roadbed limit of a cut section or within the embankment section, the excavation must be backfilled using approved layer thicknesses of material acceptable to the Department, to the top of the subgrade. Material must be compacted to an acceptable density with approved equipment.
• Outside roadway. The backfill for excavated areas must be compacted to an approved density with acceptable material and the upper surface level with the original surface. The surface must be treated, if required, in order to leave the surface in essentially the same condition as it was prior to the excavation. All surplus material and trash must be removed and disposed of in a lawful and proper manner. The work area must not be left in an unsightly condition.