Excavation and trenching - Ohio

Ohio is under federal OSHA jurisdiction, which covers most private sector workers within the state. State and local government workers are not covered by federal OSHA.

Underground utilities

Excavators in Ohio must submit a notice to locate to Ohio’s One-Call Utility Protection Service prior to excavation, which service notifies owners of underground utilities so that they can locate and mark their utilities to prevent damage, interruption of service, and injury to excavation workers. The notification rules and obligations of excavators, the one-call service, and facility owners are found at ORC Ann. 3781.25 - 3781.36.

General rules for trenches and excavations

Utility notice and location. Utility companies and municipally owned utilities will be contacted and advised of proposed work prior to the start of actual excavation. Prior to opening an excavation, effort will be made to determine whether underground installations, i.e., sewer, telephone, water, fuel, electric lines, etc., will be encountered and, if so, where such underground installations are located.

Mechanical digging near live electrical conductors. An employee may not use mechanical digging or trenching equipment within three feet of an energized underground electrical conductor whose location is known unless the conductors are protected by concrete ducts or equivalent protection.

Backfilled areas or vibrations. Where trenches or excavations are made in locations adjacent to backfilled trenches or excavations or where trenches or excavations are subjected to vibrations from any source, such as railroad or highway traffic or the operation of machinery, additional precautions by way of shoring and bracing must be taken to prevent slides or cave-ins.

Undercutting. Undercutting of the exposed faces of trenches or excavations is not permitted unless the exposed faces of such undercutting are supported by one or more of the methods prescribed for the support of exposed faces of trenches.

Material placement. Excavated material or other material must be kept at a minimum of 24 inches from the top edge of the trench or excavation. As an alternative, the employer will use effective barriers or other effective retaining devices to prevent excavated or other materials from falling into the trench or excavation.

Wells, pits, and shafts. All wells, pits, shafts, etc., will be barricaded or covered. Upon completion of exploration and similar operations, temporary wells, pits, shafts, etc., will be backfilled.

Trenches

Exposed faces. The exposed faces of all trenches more than five feet high will be shored, laid back to a stable slope, or some other equivalent means of protection will be provided where employees may be exposed to moving ground or cave-ins.

Unstable or soft material. Sides of trenches in unstable or soft material, five feet or more in depth, will be shored, sheeted, braced, sloped, or otherwise supported by means of sufficient strength to protect the employees working within them.

Hard compact soil. Sides of trenches in hard compact soil, including embankments, must be shored or otherwise supported when the trench is more than five feet in depth and eight feet or more in length. In lieu of shoring, the sides of the trench above the five-foot level may be sloped to preclude collapse but will not be steeper than a one-foot rise to each one-half-foot horizontal.

Condition of materials. Materials used for sheeting and sheet piling, bracing, shoring, and underpinning, will be in good serviceable condition, and timbers used will be sound and free from large or loose knots, and will be designed and installed to be effective to the bottom of the trench.

Trench bracing and shoring. Minimum specifications for trench bracing and shoring will be in accordance with table 26-2 in OAC Ann. 4123:1-5-26. The vertical planks in the bracing system will extend at least to the top of the trench face. Braces and diagonal shores in a wood shoring system will not be subjected to compressive stress more than values given by the following formula:

• S = 1300 - 20L ÷ D
• Maximum ratio: L ÷ D = 50
• Where:
  • L = length, unsupported, in inches;
  • D = least side of the timber in inches; and
  • S = allowable stress in pounds per square inch of cross section.

When bracing or shoring of trenches is needed, the bracing and shoring will be carried out along with the excavation.

Exits. When employees are working in trenches four feet deep or more, an adequate means of exit, such as a ladder or steps, will be provided and located to require no more than 25 feet of lateral travel.

Cross braces or trench jacks. Cross braces or trench jacks must be placed in a true horizontal position, be spaced vertically, and be secured to prevent sliding, falling, or kickouts.

Equipment used in lieu of shoring or sloping. Portable trench boxes, safety cages, or sliding trench shields may be used for the protection of employees in lieu of a shoring system or sloping. Where such trench boxes or shields are used, they will be designed, constructed, and maintained in a manner which will provide protection equal to or greater than the sheeting or shoring needed for the trench and will extend at least to the top of the trench face.

Backfilling and removal of trench supports. Removal of trench supports, and backfilling must progress together from the bottom of the trench. Jacks or braces will be released slowly, and, in unstable soil, employees will clear the trench before pulling out the jacks or braces with ropes.

Excavations

Shoring or sloping required. The walls and faces of all excavations in which employees are exposed to danger from moving ground will be guarded by a shoring system, sloping of the ground, or some other equivalent means.

Qualified design and specifications. Supporting systems, i.e., piling, cribbing, shoring etc., must be designed by a qualified person and meet accepted engineering specifications.

Conditions requiring flattening. Excavations sloped to the angle of repose will be flattened when an excavation has water conditions, silty materials, loose boulders, and areas where erosion, deep frost action, and slide planes appear.

Accepted engineering specifications. Sides, slopes, and faces of all excavations will meet accepted engineering specifications by scaling, benching, barricading, rock bolting, wire meshing, or equally effective means.

Sound materials required. Materials used for sheeting, sheet piling, cribbing, bracing, shoring, and underpinning will be in good serviceable condition, and timbers will be sound, free from large or loose knots, and of proper dimensions.

Underpinning walls. Excavations below the level of the base of the footing of any foundation or retaining wall are not permitted, except in hard rock, unless the wall is underpinned, and appropriate precautions are taken to ensure the stability of adjacent walls.

Operation of power equipment. If it is necessary to place or operate power shovels, derricks, trucks, materials, or other heavy objects on a level above and near an excavation, the side of the excavation will be sheet-piled, shored, braced or sloped as necessary to resist the extra pressure due to such super-imposed loads.

Use of mobile equipment. When mobile equipment is utilized or allowed adjacent to excavations, substantial stop logs or barricades will be installed.

Walkways and bridges. Where employees or equipment cross over excavations, walkways or bridges with standard guardrails must be provided.