The hoses are designed to provide low resistance to flow of the breathing gas.

Divers also use a similar device to measure the partial pressure of oxygen in their breathing gas.

When a person breathes, the air or other breathing gas dissolves into the blood from the lungs.

Air is the most common and only natural breathing gas.

Attempts would be made to extract breathing gas from Moon rocks, which on average are 41 percent oxygen.

The breathing gas then passes through a hose to the second stage.

With helium-based breathing gases the stop depths may start deeper.

The company experimented with the use of Hydrogen in the divers' breathing gas.

However, there was another reason for the interest in using hydrogen in a breathing gas.

Zetterström first described the use of hydrogen as a breathing gas in 1943.