Confined space rescue

Confined space rescue is a subset of technical rescue operations that involves the rescue and recovery of victims trapped in a confined space or in a place only accessible through confined spaces, such as underground vaults, storage silos, storage tanks, or sewers.

Confined space rescues can be technically challenging due to the environment in which they occur. Confined spaces are often narrow and constricting preventing easy access by rescuers. They are usually either unlit or poorly lit so rescuers must provide their own light source. Finally, confined spaces often contain hazardous materials in liquid or gas form which can be harmful or fatal to humans.

These hazards can be fatal as they create a limited window in which to perform a rescue. The general rule is that after four minutes without oxygen, a person in a confined space will likely suffer asphyxia resulting in either brain damage or death. The urgent need to rescue someone from a confined space often leads to ill-prepared rescue attempts. Two-thirds of all of deaths occurring in confined spaces are attributed to persons attempting to rescue someone else.

There are three categories of confined space rescue: self rescue, non-entry rescue and entry rescue.

In a self-rescue, much as the name suggests, the individual recognizes a critical condition or symptoms of exposure and exits the space on his or her own. Alternatively, an entry monitor, who is outside of the space, may recognize a new hazard and order individuals to leave the space before they are affected. This is the preferred rescue method as confined space hazards can quickly incapacitate or kill an individual. An individual can almost always exit a confined space in far less time than it takes to wait for someone to come in and retrieve them.

A non-entry rescue involves attempting to extricate an incapacitated person without having anyone else enter the confined space. This can be done via a safety line attached to the personnel in the confined space or by grabbing the personnel with a rope, strap or pole and pulling them to safety.

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