Excavation Safety Hazards and OSHA Standards

What is Excavation Safety?

Excavation safety is a standardized set of safety precautions for trenching and excavation to eliminate hazards and control risks in compliance with regulations. It is also referred to as Trenching and Excavation Safety, as often cited by the US Occupational Safety and Health Administration (OSHA).

What are the Hazards in Excavation?

Excavation work exposes workers to physical and atmospheric threats due to their unstable environment. Here are some of the common hazards associated with excavations:

• The collapse of the sides of the excavation

• Materials falling onto people

• Falls, either people or vehicles

• Nearby structures collapsing into the excavation

• Electrocution, explosion, blasts, gas leak, or flooding, caused by damage to underground services

What are OSHA Excavation Standards?

OSHA excavation standards are specifications of requirements for trenching and excavation, including protective systems. In US federal regulations, OSHA standards for excavations and backfilling are specifically found in Title 29 (Labor) Part 1926 (Safety and Health Regulations for Construction) Subpart P (Excavations), or 29 CFR 1926 subpart P. The excavation regulation also contains appendices for the following:

• Soil Classification

• Sloping and Benching

• Timber Shoring for Trenches

• Aluminum Hydraulic Shoring for Trenches

• Alternatives to Timber Shoring

• Selection of Protective Systems

What are the Safety Measures for Excavation?

The Bureau of Labor Statistics reported around a 70% decline in fatalities from trench collapses in 2022 due to strengthened measures against unprotected trenches. To protect workers from injuries and fatalities, preventive measures should be implemented when workers begin excavating.

According to OSHA, general safety measures to follow should cover the following:

• Establish protective systems like benching, sloping, shoring and shielding.

• Avoid collapsing by supporting the sides by either battering them or with sheets.

• Store materials from the excavation at a safe distance from the excavation. This will help reduce the risk of them falling onto people.

• Add barriers to excavation as a precaution to avoid people falling into the excavation.

• Keep vehicles completely out of the excavation area. However, if required, the use of barriers and stop-blocks should help mitigate that danger.

• Use cable, pipe, and service plans to ensure that underground services are known so they can be marked on the ground or, ideally, the area avoided entirely.

• Around the areas where there are underground services, avoid mechanical equipment and instead use spades and/or shovels.

• Avoid picks and forks as they are more likely to pierce cables and pipes.

• Avoid flooding by ensuring that there is appropriate pumping equipment so that any water that seeps into the excavation can be easily pumped out to a safe area.

Workers should also keep in mind the following procedures to perform excavations safely:

• Inspect trenches daily before work begins. Don’t go near an unprotected trench. Excavation safety software can help you ensure that your trenches are safe to work in by providing key safety measures and protocols to follow.

• Check weather conditions before work, be mindful of rain and storms.

• Keep heavy equipment away from trench edges.

• Be mindful of the location of utilities underground.

• Always wear proper protective equipment.

• Don’t work beneath raised loads.

• Conduct atmosphere tests. If low oxygen and toxic gases were detected, workers must not enter the trench.

• Use a checklist to perform regular self-inspections and risk assessments.

Examples of Excavation Protection

OSHA requires employers to implement protective measures for the safety of employees, contractors, and subcontractors before they can work on and near excavations. Here are some examples of excavation protection:

• Structural ramps – whether for the exclusive use of employees or of equipment around excavations, structural ramps must be built according to the design of a competent person.

• High-visibility vests – employees who are not only working around excavations but are also exposed to public traffic must wear high-visibility vests or clothing with similar reflective material.

• Warning signs – mobile equipment operators who do not have easy visibility of the edge of excavations should be able to see warning signs such as barricades which will indicate proximity to excavations.

• Testing – the condition of the atmosphere in and around excavations must be tested to ensure that it is safe even before employees are allowed to work at the site.

• Emergency equipment – equipment such as stretchers, harness, etc. should be available in case of an emergency.

Excavation Safety Toolbox Talk Topics

Another way to help reinforce excavation safety is by conducting toolbox talks regularly. Listed below are sample ideas of relevant excavation safety topics you can talk about with your team:

• Safe Excavation Access and Egress

• Preventing Displacement of Ramps and Runways

• Safety Tips for Sloped and Benched Excavations

• Detecting Signs of Hazardous Atmosphere

• Precautions for Exposure to Vehicular Traffic

• Safety Measures for Exposure to Falling Loads

• Protection from Water Accumulation-related Hazards

• Accepted Engineering Practices for Specific Excavation Sites

• Application of Tabulated Data by Registered Professional Engineers

• Basics of Emergency Rescue Equipment