I can comment fully and completely on the fire service side - I know nothing about hospitals.
I've been a volunteer firefighter for 12 years and can tell you everything there is to know about SCBA (Self Contained Breathing Apparatus), (SCUBA gear minus the underwater part) compressors and the cascade systems they use to fill there cylinders with.
In the US, every year over the last 8 or so years, Congress has appropriated several hundred million dollars for fire departments to upgrade equipment. You might have heard of the AFG (Assistance to FireFighter's Grant) program, administered by the Department of Homeland Security. One of the priority equipment items is SCBA, compressors and cascade systems.
The good part for you is that fire departments that never could afford to own such compressors and cascade systems now have them. In some parts of the country even the little hillbilly hick departments have them. (That's us - I wrote the grant for ours!)
Lets talk about compressors - nearly all of the new compressors going in fire departments these days are 5000psi or higher. Some of the older compressors might only go to 3000psi.
Most fire departments use 45cu ft SCBA cylinders (OSHA 30 minute rating) at either 2216psi or 4500psi. (Same CU FT cylinder - different physical cylinder sizes.) Some also use 66cu ft or 88cu ft cylinders (OSHA 45 minute and 60 minute ratings, respectively) at 4500psi for longer duration incidents - hazmat, commercial building fires, ect.
Also as a note - fire departments don't typically talk about SCBA cylinders in terms of cu ft - they talk about OSHA minute ratings. "Firefighter Jim need to change out from a 30 minute to an hour long cylinder if he is going to suit up in the level A."
So your first question is what pressure can the donor fire department fill at? What pressure tanks do you need to have filled? If you have an old steel 72 to fill at 2250psi that shouldn't be an issue anywhere. Will the fire department have an issue if you show up and want to fill 2 pair of 119cu ft doubles, at 3442psi? They might - by the fire department's standards that is a lot of air.
For fire department's it is recommended that they fill their SCBA with CGA Grade D air or better. Most fire departments fill and test to the CGA Grade E air since many fire departments have dive teams or might have to fill tanks for dive teams called into their districts, so it just makes things easier. SCUBA requires CGA Grade E air or better.
So the next question is - Will the fire department be able to provide you with Grade E air? Most can - but most also won't have a clue what you are talking about if you ask them if they have Grade E air. All they know is weather is "PASSES" or "FAILS" the quarterly testing.
If you are looking for NAUI Grade E Modified air or O2 clean air - for partial pressure Nitrox filling - you are probably going to have an issue since I don't know of any fire departments that test there air to that standard. BUT - What you might be able to do is look at the test results and compare it to the standards below and see if it meets the standard.
What follows is the testing standards for Grade E and Modified Grade E Air:
Grade E air is a Compressed Gas Association (CGA) standard that is used in scuba. The air is clean enough to breathe but not clean enough for use in high-pressure high-oxygen mixing.
* Oxygen: 20% to 22% (balance of gas predominantly nitrogen)
* Water vapor: May vary depending on intended use
* Condensed hydrocarbons: 5 mg/m 3
* Gaseous hydrocarbons (methane): 25 ppm
* Carbon monoxide: 10 ppm
* Carbon dioxide: 1000 ppm
* Odor: none
* Sampling Frequency: Quarterly
* Lab Analysis: Recommended
Modified Grade E air is a NAUI standard used by many in the scuba industry. Usually, Grade E air is run through an additional filtration process (a/k/a ÅÉyperfiltered) to reduce the hydrocarbon content, making it more suitable for use in partial pressure blending.
* Oxygen: 20% to 22% (balance of gas predominantly nitrogen)
* Water vapor:128 ppm (v/v) -40 ŽºF Dew Point
* Condensed hydrocarbons: 0.1mg/m3
* Gaseous hydrocarbons (methane): 25 ppm
* Solid particulate: less than 2 microns
* Carbon monoxide: 2 ppm
* Carbon dioxide: 500 ppm
* Odor: none
* Sampling Frequency: Quarterly
* Lab Analysis: Recommended
Hopefully that should make the fire departments abilities clearer.
Dave
