Lung Demand Regulator

A lung demand regulator comprising a valve assembly, the valve assembly comprising:

• a regulator valve apparatus for regulating a flow of breathing gas, the regulator valve apparatus being actuatable between a closed position in which no flow is permitted and an open position in which flow is permitted;
• and
• a lockout mechanism configurable in:
• a lockout configuration in which the regulator valve apparatus is secured in the closed position;
• and
• a release configuration in which the regulator valve apparatus is freely moveable,
• wherein the lockout mechanism comprises a spring plunger,
• wherein a moveable element of the spring plunger is configured to axially extend from a body of the spring plunger in the lockout configuration and in the release configuration, so as to retain the lockout mechanism in either of the lockout configuration and the release configuration, and
• wherein the moveable element of the spring plunger is configured to be depressed by a portion of the lockout mechanism during movement of the lockout mechanism between the release configuration and the lockout configuration, so as to resist movement of the lockout mechanism between the release and lockout configurations.

A breathing apparatus comprising a lung demand regulator,, wherein the lung demand regulator comprises a valve assembly, the valve assembly comprising:

• a regulator valve apparatus for regulating a flow of breathing gas, the regulator valve apparatus being actuatable between a closed position in which no flow is permitted and an open position in which flow is permitted;
• and
• a lockout mechanism configurable in:
• a lockout configuration in which the regulator valve apparatus is secured in the closed position;
• and
• a release configuration in which the regulator valve apparatus is freely moveable,
• wherein the lockout mechanism comprises a spring plunger,
• wherein a moveable element of the spring plunger is configured to axially extend from a body of the spring plunger in the lockout configuration and in the release configuration, so as to retain the lockout mechanism in either of the lockout configuration and the release configuration, and
• wherein the moveable element of the spring plunger is configured to be depressed by a portion of the lockout mechanism during movement of the lockout mechanism between the release configuration and the lockout configuration, so as to resist movement of the lockout mechanism between the release and lockout configurations.