Field-Testing Stage Reached by NASA Breathing Apparatus Development Project
What’s happened to the lighter-weight, longer-lasting, self-contained breathing apparatus announced a year ago by the National Aeronautic and Space Administration at the Johnson Space Center in Houston?
NASA officials indicated that they are going ahead with a program getting units into the field for testing by fire fighters. The spokesmen emphasized that they considered field evaluation most important to the future of the NASA breathing apparatus concept. Three fire departments will be selected to give the units a workout under actual fire fighting conditions.
Patrick McLaughlan, of the crew systems division at the Johnson Space Center, regards field testing as “a good opportunity to shake the bugs out of the system” before the units are commercialized. The testing, he said, will seek to demonstrate if the system is rugged enough for use by fire fighters. This will set the stage for commercialization. McLaughlan said that it was most important that manufacturers take over the breathing apparatus design developed by NASA and place it on the market.
“Otherwise, it is all for naught,” McLaughlan commented.
Data for manufacturers
Any manufacturer can take over the NASA breathing apparatus design and place the self-contained unit in production. After the field testing, the drawings will be updated with any changes that the testing makes necessary. NASA plans to distribute reports on the tests, the updated drawings and other pertinent documents to any commercial manufacturer interested in producing similar units. There are no patent rights involved.
Under a contract with NASA, Scott Aviation had a major role in development work on the experimental breathing apparatus.
Field testing awaited
Experimental units under the contract have all been delivered to NASA and now it is a matter of waiting for the results of the field testing. It was learned that one of the delays in field testing was the desire to have an engineer in the field to handle whatever problems may arise during the test period.
In the early stages of developing a system, liquid air and liquid oxygen systems were investigated by the scientists, but a “horrible logistics problem” was foreseen, McLaughlan disclosed. He added that a chemical breathing system is “really an optimum system from the point of weight,” but it has problems with low temperature operation. Furthermore, he explained, heat is generated by a chemical system and the breathing air becomes warm.
McLaughlan said he was confident that the NASA system can support the fire fighter in his working needs.
The NASA breathing apparatus with a 60-scf aluminum cylinder with a fiber glass overwrap, described in the January 1974 Fire Engineering, page 47, originally was designed for a maximum stored air pressure of 4000 psi. This full-cylinder pressure has now been raised to 4500 psi, thereby necessitating the use of a 5000-psi air compressor. With the 60-scf air cylinder, the NASA breathing apparatus weighs 26 pounds. With a 40-scf cylinder that NASA also has designed to be used with the rest of the breathing apparatus components, the total weight is 20 psi.
Air duration time
A NASA report on the breathing apparatus system stated that “in actual fire fighting conditions, (air) consumption rates in the range of 2 scf/ minute may be experienced, resulting in shorter actual durations” than the duration times noted during tests of the equipment. The average duration times reported for trained men testing the breathing apparatus were 56 minutes for the 60-scf cylinder and 40 minutes for the 40-scf cylinder.
If air consumption is figured at the high rate of 2 scf/minute, the 60-scf cylinder would last for 30 minutes, which is the time that NASA declares is the minimum time that can be expected for the apparatus under fireground conditions.