Confined spaces such as tanks, silos, vessels, pits, and underground chambers can expose workers to serious hazards, including oxygen deficiency, toxic gases, flammable atmospheres, engulfment, and restricted movement. Before entry, employers should assess the risks, identify potential energy sources, isolate hazardous equipment, and obtain the required confined space entry permit. The atmosphere must be tested by trained personnel using suitable calibrated instruments, and ventilation should be provided where necessary to maintain safe conditions. Workers should never enter a confined space without proper authorization and required safety precautions.

A safe confined space entry program should include trained and authorized workers, a designated attendant outside the space, reliable communication, suitable PPE, and a site-specific emergency rescue plan. Atmospheric conditions may need continuous monitoring, depending on the risk assessment and work conditions. Emergency rescue equipment and trained responders must be available before entry begins. Proper risk assessment, atmospheric testing, controlled entry, and effective rescue planning help prevent confined space accidents and protect industrial workers.