When should ventilation procedures begin during confined space operations?

Ventilation procedures should begin prior to entry and continue throughout the operation because ensuring a safe atmosphere is critical when working in confined spaces. Active ventilation helps to reduce the concentration of hazardous gases, vapors, or other airborne contaminants, and it can also supply fresh air to the area. Starting ventilation before entry ensures that any potentially hazardous conditions are mitigated as early as possible, decreasing the risk to workers.

Additionally, continuous ventilation during the operation helps to maintain a safe atmosphere, especially as tasks are completed or if conditions change. It is essential to keep a controlled environment, especially when workers are in the space for extended periods, which could lead to the accumulation of harmful substances. Therefore, initiating and maintaining ventilation is a proactive safety measure in confined space operations.