A Life Safety Initiative to Increase the Exit Time for Fire Service SCBA

Past experience has shown that 25 percent may not be enough to exit a structure fire.  Twenty-five percent of the common 30-minute SCBA bottle is 1125scf of air. This will provide most users with four to six minutes of air.  Is this really enough time for a firefighter to exit any structure?  Is it enough time to effect the rescue of a lost or trapped firefighter?  Despite calls for the fire service to have better ‘situational awareness’ and improved ‘air management’ skills, the remaining service-life indicator is the method by which most firefighters are warned to exit the hazard zone.

With the exit time problem being so serious, the obvious and simple solution would be to simply adjust the low air alarm upwards to provide a greater margin of safety. The problem is, federal regulation prohibits an SCBA’s low air alarm (remaining service life indicator) from notifying the user prior to 25%.

The current rule [42 CFR part 84 section 84.83 (f)] reads as follows:

Each remaining service-life indicator or warning device shall give an alarm when the remaining service life of the apparatus is reduced within a range of 20 to 25 percent of its rated service time.

This general regulation covers all users of self-contained breathing apparatus (SCBA).  The flaw of this rule is that it has an upper limit of alarm (25%).  By limiting the alarm period to this range, an SCBA cannot be made to warn the user prior to 25 percent of remaining service time.  This rule does not meet the needs of the fire service. 

This stipulation predates the adoption of 42 CFR 84 in 1995.  In fact, the 25 percent upper limit has been in place prior to 1960. The original rationale for the 25 percent stipulation is not known for certain; however, it is probably due to the following:

• When the respirator rules and regulations were originally written, they were written based upon the ‘what is’ of the day (i.e. if a respirators remaining service life indicator alarmed between 20 and 25 percent, then that is what made it into the regulation).

• The original regulations reflected the technology of the day:

1. Early SCBA cylinder technology limited bottle pressure to 1800psi, resulting in limited air volume that could be reasonably carried.  The result was a compromise in exit time in order gain maximum benefit of the SCBA for firefighting purposes.  Today’s air bottles do not pose this same limitation.

2. Prior to the 1980’s, firefighting strategy consisted of limited offensive firefighting. Today, deep offensive firefighting is the norm.

3. Firefighting protective clothing has evolved considerably since that time, allowing for much deeper offensive firefighting to occur.

4. The large and complex (vertical and horizontal) structures of today were uncommon at the time this regulation was established.

The size and complexity of today’s structures, advances in structural firefighter clothing, current firefighting tactics, and the ability to carry larger volumes of air all underscore why this rule does not meet the needs of today’s fire service.

These facts, paired with the fact that firefighters are more than twice as likely to be killed while fighting a fire in a non-residential structure(1), highlight the need to amend this rule to better address the inadequate air volumes that most firefighters carry with them into the hazard zone.

The following addition should be implemented for fire service users of SCBA’s:

Each remaining service-life indicator or warning device shall give an alarm when the remaining service life of the apparatus is reduced to no less than 25 percent of its rated service time.

This change would allow the fire service to better address when the remaining service-life indicator should be set to alarm. It would also result in ‘opening the windows’ of Exit, Self-Rescue and Rapid Intervention Team (RIT) rescue. If the remaining service-life indicator were allowed to be adjusted upwards, a set point of 50% would cause these ‘windows’ to  widen as follows:

Air volumes are measured in square cubic feet of air (scf). *HZ= Hazard Zone. Average times are estimates based on .218-.327 seconds/scf; actual time will vary by user. * Uncommon 3000psi 30-minute rated SCBA

Air volumes are measured in square cubic feet of air (scf). HZ= Hazard Zone. Average times are estimates based on .218-.327 seconds/scf; actual time will vary by user. * Uncommon 3000psi 30-minute rated SCBA

Under the current rule, the only way to increase exit time (as indicated by the remaining service-life indicator) is to increase bottle size, which in turn increases time in the hazard zone. The fire service has shunned this solution due to work stress and depth of entry issues.  The fire service has clearly demonstrated (through the continued widespread use of 30-minute bottles) the desire for a work period equal to the 3375scf air volume.  It is for this reason, that the adoption of this amendment is the only reasonable option to provide the fire service with adequate breathing air for exit or rescue, while maintaining a reasonable hazard zone operational period.

The current National Fire Protection Administration (NFPA) Respiratory Protection Standard (NFPA 1981) is not able to address this issue due the constraints of the federal regulation.

Approval of this proposed change would better serve the needs of the fire service in its quest to eliminate line-of-duty death and injury.

For more detailed information about this problem, refer to document Time To Exit.

Sponsored By The Columbus Firefighters Union IAFF Local 67