What is a major safety precaution when dealing with confined spaces?

In the context of confined spaces, monitoring for hazardous gases is a critical safety precaution because these environments often contain low oxygen levels or toxic substances that can pose serious health risks to individuals entering them. Confined spaces may trap gases such as carbon monoxide, methane, or hydrogen sulfide, which can be detrimental or even fatal upon exposure.

Prioritizing the monitoring of air quality ensures that workers are informed of any potential dangers before entering the space, allowing for necessary ventilation or protective measures to be taken. This aspect of safety is paramount as incidents related to hazardous gases are a leading cause of fatalities in confined space operations.

While ensuring visibility, checking structural integrity, and using radio communication are also important safety considerations, they do not directly address the immediate risks posed by hazardous gases, which can result in rapid impairment or serious accidents. Hence, monitoring for hazardous gases is the foremost safety precaution when working in confined spaces.