Unsafe ground conditions can introduce new hazards on outdoor job sites which can slow down projects and can also be dangerous for workers.
Poor ground conditions can have a negative impact on site safety for workers on foot and for vehicles and heavy equipment moving through the area. Unstable ground conditions create risks for workers operating cranes, aerial lifts, or any other equipment that relies on ground stability to ensure worker safety.
OSHA Standard 1910.22 Walking-working surfaces are inspected, regularly and as necessary, and maintained in a safe condition. The employer must ensure that each walking-working surface can support the maximum intended load for that surface and the employer must provide, and ensure each employee uses, a safe means of access and egress to and from walking-working surfaces.
There are various types of ground conditions that can cause problems on worksites, particularly if workers lack the proper training and equipment to deal with them. When hazardous ground conditions are hidden beneath materials, debris, or grass an even higher degree of awareness is required by all personnel.
Cracked or damaged walkways can lead to trips and falls, while embankments can pose the risk of collapse or sliding if not properly secured. Environmental debris, like fallen branches or leaves, can create slippery or unstable surfaces and exposed tree roots are potential tripping hazards
Ground holes, whether small or large, can be dangerous if not properly marked or filled in, as workers might inadvertently step into them. Rubble or debris left behind from previous work or natural disasters can create hazards if not properly cleared away, while sandy areas can lead to shifting ground and instability.
Invisible level changes, like slight changes in elevation, can cause trips and falls if workers are moving quickly and unaware of their presence. Loose soil or gravel can lead to landslides or cave-ins, rocky terrain can be treacherous and uneven or sloping terrain can lead to falls or equipment rollovers.
When severe weather moves through an area damaging winds, heavy rains, and winter storms can all create challenging ground conditions for workers. But it’s not just the weather that can cause an unsafe work environment. The ground at a job site can become difficult or even dangerous for many different reasons, including:
- Uncompacted fill when soil or other material is backfilled into a trench without compaction
- Excess water on site from rain, flooding, or operational activities that use water
- Thawing ground that was previously frozen
- Vibration from heavy machinery, equipment, or vehicles on the job site
- Sloping or uneven terrain
- Structural collapse causing hidden dangers and adding stress to the ground
- Nearby excavations may weaken the surrounding ground
- Geological activity, like an earthquake
- Unguarded holes create trip and tip-over hazards
Ground conditions can change overnight. For any outdoor job site, ground conditions should be included in the daily hazard assessment. Identify uneven or unstable areas, and then fix, cover, barricade, re-route, or make equipment adjustments accordingly to ensure worker safety.
OSHA Standard 1926.20(b)(2) [Safety and health] programs shall provide for frequent and regular inspections of the job sites, materials, and equipment to be made by competent persons designated by the employers.
Use ground protection mats over muddy, slippery, or uneven areas. Cover or guard all holes at the job site that are trip hazards for workers or tip-over hazards for equipment.
Cut steps into sloping areas on the job site to make it more manageable. Repair the steps over time as they begin to deteriorate with use.
Clear tall grass or brush on the job site that could be covering hidden dangers like holes, sharp objects, snakes, or other wildlife. Remove stones and rubble that are creating uneven ground conditions or create an alternate route for personnel and equipment.
Do not enter flooded areas on foot, when driving, or while operating equipment. It is difficult to know how stable the ground is or what hidden dangers are beneath the water. If work needs to continue in the area, pump out the water first.
Mud can very quickly create a slippery, sticky, uneven surface at the job site that makes even routine work tasks unmanageable. In muddy work areas slips, trips, and falls increase, and workers have a greater chance of injury. Traction and control are greatly reduced in muddy conditions and can increase the risk of vehicle and equipment collisions and overturn incidents.
OSHA Standard 1910.22(d)(2) Hazardous conditions on walking-working surfaces are corrected or repaired before an employee uses the walking-working surface again. If the correction or repair cannot be made immediately, the hazard must be guarded to prevent employees from using the walking-working surface until the hazard is corrected or repaired.
When muddy ground conditions are a job site nuisance use heavy equipment, like a bulldozer, to clear or level the muddy areas. The goal is to create a solid and stable ground surface that is safer for work activities. Add temporary ground protection pads or mats on foot paths to prevent slips and falls, especially at the entrances and exits to the work site.
Do not drive into excessively muddy areas or up and down slick slopes. Getting equipment stuck in the mud creates even more hazards for workers when they have to help pull the vehicle out.
While walking, if you get your foot stuck in the mud, slowly move your foot back and forth to gently work it out. Do not attempt to forcefully yank your foot out of the mud which can cause a fall and result in injury.
Keep the steps on heavy equipment clean and remove mud off your boots before climbing up into the cab. Always use three points of contact when climbing up and down.
Adequate ground conditions are required for the safe operation of heavy equipment, cranes, and any mobile elevated work platforms. Conduct a site inspection to assess ground conditions before moving equipment into an area. For self-propelled equipment that may be moved while elevated, inspect the entire area for safety and stability before operation.
OSHA Standard 1926.1402(b) Cranes and Derricks in Construction. The equipment must not be assembled or used unless ground conditions are firm, drained, and graded to a sufficient extent so that, in conjunction (if necessary) with the use of supporting materials, the equipment manufacturer's specifications for adequate support and degree of level of the equipment are met.
The floor or ground directly above a cellar or basement area may not be designed to bear the weight of heavy equipment. Take this into account before moving machinery onto this type of area.
Avoid positioning cranes or powered access platforms, like aerial lifts, too close to the edge of an excavation where the ground may be compromised and likely to collapse without warning.
Underground utilities can be impacted by the weight of equipment so ensure the ground conditions are always strong and stable enough to hold the weight of the load. Just because it’s paved, doesn’t mean it’s strong. Paved areas can hide weaker ground or shallow surfaces below.
If work cannot be moved or delayed, poor ground conditions may require additional foundations such as pads or mats to spread the weight and stabilize the load.