Aerospace Medicine Technical Reports
FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute
Report No: DOT/FAA/AM-04/3
Title and Subtitle: Performance Criteria for Development of Extended Use Protective Breathing Equipment
Report Date: February 2004
Authors: Garner RP, Utechtt JS
Abstract: The Federal Aviation Administration (FAA) requires under Federal Aviation Regulation (FAR) 121.337 that crew protective breathing equipment (PBE) for smoke and fume protection is installed aboard aircraft and that crewmembers be trained in the proper use of PBE (FAR 121.417). A variety of designs currently exist that meet the requirements of these regulations. However, the threat posed by atmospheric contamination in an environment that cannot be quickly escaped suggests that extending the protective capabilities of PBE devices beyond what is mandated by the FAA may be beneficial in aviation and other arenas.
These experiments were conducted to evaluate the use of one style of PBE in terms of potential for long-term (>20 min) use and to identify issues critical to long-term use. A closed circuit PBE device utilizing lithium hydroxide (LiOH) technology for carbon dioxide (CO2) removal was tested. The capability to supply fresh oxygen to the user had been incorporated into the prototype design. Breathing simulator testing clearly demonstrated that CO2 levels during use were consistent with theoretical values and represented the limiting factor for long-term wear when coupled with the �ad libitum� use of oxygen.
As expected, metabolic CO2 production rate was the primary factor limiting time of use in the prototype testing performed. From a practical standpoint, it was also clear that consistent and effective means of oxygen delivery and temperature control need to be developed. If these issues can be successfully addressed in terms of meeting a metabolic demand anticipated for a given operational environment, PBE capable of providing from 2 to 5 hours of protection to the user may be a viable possibility.
Key Words: Protective Breathing Equipment, Lithium Hydroxide, Carbon Dioxide
No. of Pages: 8
Civil Aerospace Medical Institute
Report No: DOT/FAA/AM-04/3
Title and Subtitle: Performance Criteria for Development of Extended Use Protective Breathing Equipment
Report Date: February 2004
Authors: Garner RP, Utechtt JS
Abstract: The Federal Aviation Administration (FAA) requires under Federal Aviation Regulation (FAR) 121.337 that crew protective breathing equipment (PBE) for smoke and fume protection is installed aboard aircraft and that crewmembers be trained in the proper use of PBE (FAR 121.417). A variety of designs currently exist that meet the requirements of these regulations. However, the threat posed by atmospheric contamination in an environment that cannot be quickly escaped suggests that extending the protective capabilities of PBE devices beyond what is mandated by the FAA may be beneficial in aviation and other arenas.
These experiments were conducted to evaluate the use of one style of PBE in terms of potential for long-term (>20 min) use and to identify issues critical to long-term use. A closed circuit PBE device utilizing lithium hydroxide (LiOH) technology for carbon dioxide (CO2) removal was tested. The capability to supply fresh oxygen to the user had been incorporated into the prototype design. Breathing simulator testing clearly demonstrated that CO2 levels during use were consistent with theoretical values and represented the limiting factor for long-term wear when coupled with the �ad libitum� use of oxygen.
As expected, metabolic CO2 production rate was the primary factor limiting time of use in the prototype testing performed. From a practical standpoint, it was also clear that consistent and effective means of oxygen delivery and temperature control need to be developed. If these issues can be successfully addressed in terms of meeting a metabolic demand anticipated for a given operational environment, PBE capable of providing from 2 to 5 hours of protection to the user may be a viable possibility.
Key Words: Protective Breathing Equipment, Lithium Hydroxide, Carbon Dioxide
No. of Pages: 8
Last updated: Friday, June 1, 2012