At what depth should trenches start being tested for atmospheric conditions?

Trenches should start being tested for atmospheric conditions at a depth of 4 feet. This depth is significant because it aligns with safety protocols aimed at preventing hazards associated with confined spaces. Atmospheric testing at this depth is crucial to identify potential dangers such as low oxygen levels, hazardous gases, or toxic vapors that could pose serious risks to workers.

Testing for atmospheric conditions at 4 feet deep allows for early detection of these hazards, helping to ensure that appropriate safety measures, such as ventilation or the use of personal protective equipment, can be implemented. The choice of this specific depth is often based on industry standards and regulations that prioritize worker safety in excavation and trenching operations.

Choosing a depth less than 4 feet might not adequately consider the potential for dangerous atmospheric conditions, while a greater depth, though potentially valid, is not the established threshold for initiating atmospheric testing as required by safety guidelines.