What action is recommended when hazardous atmospheres are expected in an excavation?

Conducting air testing before entry into an excavation where hazardous atmospheres are expected is essential for ensuring the safety of personnel. This action helps to determine the presence of harmful gases or lack of oxygen, which can pose serious health risks. Air testing can identify toxic substances such as hydrogen sulfide, carbon monoxide, or other hazardous materials that may not be immediately visible. By assessing the air quality beforehand, appropriate measures can be taken to mitigate hazards, such as providing proper ventilation or implementing air monitoring systems. This proactive approach not only helps protect workers but also ensures compliance with safety regulations, reducing the risk of accidents and injuries during excavation operations.