1. Pit Excavation up to 3m

Provide protection by one or more of the following: Set spoils and equipment at least 2 feet back from the excavation. Use retaining devices, such as a trench box, that will extend above the top of the trench to prevent equipment and spoils from falling back into the excavation.

Top 5 excavation safety hazards

• Cave-ins. Trench collapses kill an average of two workers every month, making this a serious threat to worker safety.
• Falls and falling loads. Workers and work equipment can fall into an excavated area.
• Hazardous atmospheres.
• Mobile equipment.
• Hitting utility lines.

More excavation-related hazards

• falls into trenches or excavations.
• tripping over equipment, debris and spoil.
• excavated material or other objects falling on workers.
• exposure to underground services or overhead electrical cables.
• unstable adjacent structures.
• mishandled or poorly placed materials.

Avoid underground services and make sure not to undermine nearby structures – use safe digging practice and dig away from them. Check the excavation each day before starting work and after any event that may affect its stability. Provide safe access to get in and out. Prevent collapse – shore, bench, or batter back.

03. Safety Precaution while Excavation Work:

• Prepare firm and broad approach road.
• The nail should not be lying around, after the completion of layout work.
• Barricade the site to restrict the entry of animal and the unauthorised person on site.
• Ensure that workers are wearing personal protective equipment.

How is Excavation Done Safely?

• Inspect trenches daily before work begins.
• 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.

Types of Excavation

• Earth excavation is removal of the layer of soil immediately under the topsoil and on top of rock.
• Muck excavation is removal of material that contains an excessive amount of water and undesirable soil.
• Unclassified excavation is removal of any combination of topsoil, earth, rock, and muck.

An important step in determining the hazards in a confined space is air testing….Air quality testing

• The oxygen content is within safe limits – not too little and not too much.
• A hazardous atmosphere (toxic gases, flammable atmosphere) is not present.
• Ventilation equipment is operating properly.

Risks of working in confined spaces

• loss of consciousness, injury or death from contaminants in the air.
• a fire or explosion that kills or seriously injures.
• suffocation from oxygen deficiency.
• crushing or suffocation from something like grain, sand, flour or fertiliser if you fall into it.

Working in a confined space is dangerous because of the risks from noxious fumes, reduced oxygen levels, or a risk of fire. Other dangers may include flooding/drowning or asphyxiation from some other source such as dust, grain or other contaminant.

These regulations contain the following key duties: avoid entry to confined spaces, e.g. by doing the work from the outside; if entry to a confined space is unavoidable, follow a safe system of work; and. put in place adequate emergency arrangements before the work start.

Examples of confined space hazards exhaust gases. flammable gases. low oxygen levels. risk of engulfment by stored substances such as wheat or sand.

Poor ventilation is a hazard. And like all hazards, it poses a risk to your employees’ health and you must eliminate or control it at all costs. If you don’t, it’ll slow down productivity in your workplace and result in increased sick leave.

Confined spaces that contain liquids or flowable solids like grain, corn, or coal pose an engulfment hazard. Engulfment occurs when a person is pulled under the surface of a liquid or flowable solid, and can result in death from strangulation, constriction, or crushing.

Confined spaces include, but are not limited to, tanks, vessels, silos, storage bins, hoppers, vaults, pits, manholes, tunnels, equipment housings, ductwork, pipelines, etc.

Normal arterial oxygen is approximately 75 to 100 millimeters of mercury (mm Hg). Values under 60 mm Hg usually indicate the need for supplemental oxygen. Normal pulse oximeter readings usually range from 95 to 100 percent. Values under 90 percent are considered low.

An oxygen level below 88% can be dangerous for any period of time. An oxygen level below 85% warrants a trip to the hospital. Keep in mind that an oxygen level 80% and lower puts your vital organs in danger, so it is important to keep a blood oxygen level chart handy so you know what levels require immediate treatment.

Not Enough Oxygen: Side Effects Mental functions become impaired and respiration intermittent at oxygen concentrations that drop from 10 to 14 percent; at these levels with any amount of physical activity, the body becomes exhausted. Humans won’t survive with levels at 6 percent or lower.

The brain gets affected when the SpO2 level falls below 80-85%. Cyanosis develops when the SpO2 level drops below 67%. The normal oxygen levels in a pulse oximeter usually range from 95% to 100%. Note: Normal levels may vary if you have lung disorders.

Pulse oximeter accuracy is highest at saturations of 90-100%, intermediate at 80-90%, and lowest below 80%.