Why is it important to check for gases before entering a manhole?

Checking for gases before entering a manhole is crucial primarily to avoid potential explosions or suffocation. Manholes can accumulate hazardous gases such as methane, carbon monoxide, or hydrogen sulfide, which can be harmful or even lethal when inhaled, especially in confined spaces where ventilation is limited. Before entering, it is essential to use gas detection equipment to assess the atmosphere for dangerous levels of these gases, ensuring the safety of personnel.

The importance of this practice cannot be understated, as neglecting to check for gas can lead to serious accidents, including explosions if flammable gases are present and ignited, or suffocation from gases that displace oxygen. Safety protocols mandate that all workers be sufficiently trained to recognize these risks and take appropriate measures to mitigate them, prioritizing their safety while performing their duties.