Re: PLAN Aircraft Carrier programme..News & Views
This is ah shutoff button to stop Oxygen flow!
There are two Systems for firefighting: the under-pressure and the over-pressure System.
While in the under-pressure System the firefighter has to create a under-pressure inside the mask by breathing in all the time to open a valve which Releases the Oxygen flow (valve is closing again), in the over-pressure System the Oxygen flow is all the time present, so you have all the time a small over-prssure inside the mask. By breathing in the pressure decrease and more Oxygen will flow into the mask to hold the pressure inside. Benefit of the overpressure System is that in case of a leaky mask the smoke is not able to get into the mask and the outcoming Oxygen is also alerting the firefighter that there is any leak (you can feel it on your Skin and possible also hear the flow).
So, in this case we can see a over-pressure System and the button is to close a valve inside which stops the Oxygen flow to take off the mask - otherwise the Oxygen would flow all the time while not wearing the mask like in this Situation in the photo.
By breathing in the first time the valve will automatically open again and the over-pressure System is active.
What's that square red button on that protective oxygen mask for...anyone knows?
This is ah shutoff button to stop Oxygen flow!
There are two Systems for firefighting: the under-pressure and the over-pressure System.
While in the under-pressure System the firefighter has to create a under-pressure inside the mask by breathing in all the time to open a valve which Releases the Oxygen flow (valve is closing again), in the over-pressure System the Oxygen flow is all the time present, so you have all the time a small over-prssure inside the mask. By breathing in the pressure decrease and more Oxygen will flow into the mask to hold the pressure inside. Benefit of the overpressure System is that in case of a leaky mask the smoke is not able to get into the mask and the outcoming Oxygen is also alerting the firefighter that there is any leak (you can feel it on your Skin and possible also hear the flow).
So, in this case we can see a over-pressure System and the button is to close a valve inside which stops the Oxygen flow to take off the mask - otherwise the Oxygen would flow all the time while not wearing the mask like in this Situation in the photo.
By breathing in the first time the valve will automatically open again and the over-pressure System is active.