The Lung Powered ScrubberTM was designed for removing carbon dioxide from a chamber atmosphere. The silicone mask and canister are stored in a nylon storage bag. This technology has been used in the commercial diving industry and military submarines for over fifty years. The Lung Powered ScrubberTM can be used without any extensive training and will protect the user for many hours on one canister. The canister has a built-in PH indicator. The chemical is white and will turn violet in color while being used. The unit is “lung powered” and requires very little maintenance & no electricity. The old canister can be changed by simply removing the hose clamp and installing a fresh canister. A Lung Powered ScrubberTM should definitely be a standard part of your chamber emergency backup system.