Escape respirator Wikipedia
Escape respirator is a portable appliance regenerating breathable air to help provide respiratory protection for emergency escape from zones containing harmful gases. A cross-breed between a gas mask and a respirator, the emergency respirator is used extensively in mining and chemical industries.
The name of the appliance stems from the fact that the emergency respirator is not designed to provide clean air for extended periods of time. Instead, it is a breathing device allowing people working in dangerous conditions escape in case of an emergency, such as a leak of methane, hydrogen sulfide or other dangerous gasses. Usually the escape respirators provide protection for under one hour.
Depending on the type, some escape respirators include a breathing gas cylinder, chemicals producing oxygen or a combination of the two.