WORKING IN CONFINED SPACES

Confined spaces are defined as those with limited means of entrance and exit. Typically, they provide an area just large enough for one person to perform a specific task. At WASA, several categories of workers engage in tasks, which require that they enter confined spaces. They include wastewater workers who must enter manholes to maintain and repair sewers, and those who clean wet wells and re-circulation chambers; workers who clean large service reservoirs, clear wells and clarifiers on water treatment plants. Under certain circumstances, the repair, replacement and laying of underground pipes and valves in deep trenches can be regarded as confined space work. The possibility of trench walls collapsing is real, and special techniques of trenching and shoring have to be employed to create safe working conditions.

In light of the small space, workers only have a limited supply of air and can easily collapse. Measures to supply adequate air and purge small workspaces of stale air must be employed. In fact, monitoring equipment that checks available oxygen levels and detect possible toxic or explosive gases need to be utilized in many cases.

Additional lighting is often necessary to further increase safety. Communication with the worker in the confined space must always be maintained with someone on the outside. The person who appears to be idly looking on at work going on within the hole, is actually performing a critical function and must be trained in emergency measures including first aid and CPR.