Method and Apparatus for Automatically Maintaining a Desired Level of Oxygen in a Refuge

A refuge chamber comprising:

• an enclosure which provides a protected environment for at least one person to be in;
• an oxygen supply in communication with the enclosure;
• an apparatus disposed in the enclosure for automatically controlling the oxygen level in the enclosure without human interaction, monitoring or adjustment having an oxygen sensor, a valve connected to the oxygen supply with a quick release hose, and a plurality of relays in communication with the sensor that control when the valve is open or closed regarding release of oxygen by the valve from the oxygen supply;
• and
• a manifold disposed in the enclosure to which the quick release hose can be disconnected if the apparatus stops operating so oxygen can continue to be released from the oxygen supply, the manifold providing manual control by the person of the oxygen level when the quick release hose is connected to the manifold.

A method for controlling a level of oxygen in a closed environment from an oxygen supply comprising:

• detecting with an oxygen sensor the level of oxygen in the closed environment is below a first predetermined level;
• automatically opening with a plurality of relays whose operation is controlled by the level of oxygen detected by the sensor without human interaction, monitoring and adjustment a valve which is in communication with the sensor and the oxygen supply to release oxygen from the oxygen supply into the environment;
• detecting with the oxygen sensor the level of oxygen in the closed environment is above a second predetermined level;
• and
• automatically closing with the plurality of relays without human interaction, monitoring and adjustment the valve to stop oxygen from being released from the oxygen supply into the environment.