Is Your SCBA Dangerous?

Is Your SCBA Dangerous?

FEATURES

PROTECTIVE CLOTHING

Making sure that your SCBA is well-maintained and meets safety standards should be as natural as, well, breathing.

Is your self-contained breathing apparatus dangerous? When you go into a burning building using air from the tank on your back, are you walking into a potentially deadly trap with a false sense of security? Have firefighters died because their SCBA was the weak link in their protective ensemble? These are very disturbing questions, but questions that must be asked in the light of some distressing evidence.

Imagine finding yourself surrounded by fire, knowing that you had 20 or maybe 30 seconds to escape. Then imagine having the air cylinder fall off your back because the straps melted in 10 seconds. Think about having the lens fall out of your facepiece, or watching it melt or crack before your eyes, or watching the flexible air tube between the regulator and the facepiece burn through. These are all things that have happened—and they could happen to you. That’s a very high-percentage bet: The regular and routine use of SCBA has had the greatest positive impact on firefighter health and safety of any advance in this century. The danger lies in that we’ve become so confident through routine, successful use of SCBAs that we are complacent in situations that, under the wrong circumstances, could be instantly fatal.

There is a very real possibility that some firefighter deaths, serious injuries, and close calls have resulted from SCBA failures.

No one should be more concerned about the reliability of an SCBA than the individual who is going to wear it into an area where only one unprotected breath can be fatal. We depend on an SCBA to provide a safe supply of air in a hostile environment, and we bet our lives that it will work perfectly every time.

Consider these questions:

Does your SCBA meet the most current standards?

Are even the most current standards adequate for the conditions you face?

Is your SCBA properly designed and maintained to protect you when you get into a situation in which your life depends on it?

The protective ensemble

It’s not easy to define the conditions that firefighters will face inside a burning building. The conditions range from light smoke to zero visibility and from freezing cold to flaming hot. There’s always a high probability that toxic gases in unknown combinations and concentrations will be present. With all of these unknowns, we have to anticipate the worst, or at least the worst that we could anticipate surviving. We want our protective ensemble to be the difference between life and death when the conditions around us say death.

The research that went into Project FIRES concluded that a firefighter should have enough protection to escape from a sudden flashover if a reasonably quick exit is available. This was defined to be protection from a heat flux of 2 calories per square centimeter per second for a period of 17.5 seconds. This is the origin of the Thermal Protective Performance (TPP) rating of 35.

According to the mathematics, if you wear a protective ensemble with a TPP of 35 and you’re caught in a flashover of this intensity, you should have 17.5 seconds to escape without serious injury. “Without serious injury” means no second-degree burns.

If you’re wearing the proper level of protective clothing designed to protect your body from burns in a flashover or backdraft, how can you be sure that your SCBA will protect your vital respiratory system from those same conditions? If you have a 15to 20-second time period to escape from the flames before you are seriously burned, an SCBA that fails in 10 seconds could mean that you die. There are two kinds of firefighters who know about that kind of experience: some who are lucky to be alive and some who are dead.

The fire environment

Unfortunately, we can’t exercise much control over the intensity of a flashover. Research has indicated that levels up to 4 calories per square centimeter per second can be anticipated, depending on the fuel, the air supply, and the size of the room. If the exposure is doubled, the time to escape is cut in half. We’re looking at providing protection in a 10to 20-second exposure to full flashover conditions.

If we’re willing to accept some second-degree burns—and most of us would find that preferable to death —the time could be longer. It’s very hard to say how much longer, but fire provides a great incentive to move quickly, and even people with secondor third-degree burns usually keep on moving if they can find a way out of the fire. The charred bodies we find in the burned-out ruins are usually the ones who had no way out or who did not have protection for their respiratory systems. One breath of superheated fire gases will sear the lungs; a few whiffs of toxic products of combustion will stop most desperately fleeing humans.

The critical factor that we’re seeing in many firefighter deaths is that they could not get out in time when a flashover occurred, when a backdraft surrounded them with flames, or when a similar situation occurred. In many cases they have been almost within reach of safety, but something prevented them from escaping: either they weren’t using respiratory protection or their breathing apparatus failed to protect them. In several cases it appears that the SCBA was the weak link in their protection.

Remember, however, that the most efficient, best-maintained SCBA in the world is of little use when taken into a fire environment for which it is not designed.

Design standards

Self-contained breathing apparatus has been subject to the approval of the National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA) for several years. The first approval process for breathing apparatus was established by the U.S. Bureau of Mines, part of the Department of the Interior and the predecessor of today’s MSHA. The MSHA standards are based on mine rescue requirements and date back almost 60 years. They contemplate working in a toxic atmosphere, but not the atmosphere that firefighters consider routine.

Phoenix Fire Department SCBA Inspection and Maintenance Schedule

Daily check at change of tours:

1. Check air bottle gauge. (Below 2,000 psig – remove from service)
2. Check air cylinder for visible damage. (See Note A.)
3. Turn on air supply valve. Listen for air leak.
4. Check high-pressure air hose and couplings for wear or leaks. Faulty “O” ring on coupling to air cylinder is common cause of air leak.
5. Check reading on regulator gauge. Reading consistent with cylinder gauge. (See Note B.)
6. Check face mask and breathing tube to mask for cracks and tears. (See Note C.)
7. Don SCBA assembly.
8. Put on facepiece, check for seal. Check exhalation valve for proper operation.
9. Open yellow mainline valve fully, check operations.
10. Close yellow valve on regulator. Crack red bypass valve on regulator. Check operations. Close red valve.
11. Remove SCBA assembly. Shut control valve on cylinder.
12. Crack yellow valve on regulator to slowly bleed off air in highpressure hose.
13. Warning device will activate as air bleeds off. Check operation.
14. Shut yellow valve for storage.
15. Clean and/or disinfect facepiece if necessary.
16. Place facepiece in protective bag and store SCBA assembly in rack in “ready” condition.

Note A: Inspect the cylinder for cuts, digs, gouges, abrasions, dents or cracks. Also look for signs of heat damage. Look for loose bands of fiber peeling from the cylinder. Check the valve assembly for damage. In all cases, remove the cylinder from service for further testing by a testing agency.

Hydrostatic Testing Agency Guidelines —

Cylinder will be condemned and replaced if there are:

1. flaws or cuts in overwrap of a fully wound composite cylinder exceeding .09 inches in depth;
2. flaws or cuts in overwrap of hoop-wound cylinder exceeding .01 inches in depth;
3. abrasions in fully wound composite cylinders exceeding .045 inches in depth;
4. abrasions in hoop-wound cylinders totaling more than 4 square inches or exceeding .005 inches in depth.

Note B: A difference in gauge readings should be reported. Replace the cylinder and perform this test again. This will indicate which gauge (if any) is defective. In emergency situations, the lower reading will be considered as the air supply available.

Note C: Additional facepiece/assembly checks:

1. Rubber—distortion, dirt, cracks, tears, holes, tackiness.
2. Harness—breaks, loss of elasticity, missing buckles and straps.
3. Serrations—wear.
4. Lens—cracks, scratches, tight seal.
5. Exhalation valve—visual check for cleanliness.
6. Breathing tube—cracks in corrugations, missing or loose hose connections.
7. Coupling nut—cracks, distortion, gasket in place, loose.

Quarterly check, performed by certified technicians in fully equipped service area or vehicle:

1. Inspect entire unit and cylinder.
2. Flow-test regulator on test machine to verify positive-pressure and air flow rate.
3. Check low-pressure alarm, replace “O” rings, recalibrate.
4. Replace parts as needed (including decals).
5. Clean entire unit.
6. Record all work performed.

The second approval agency, NIOSH, was created as part of the U.S. Public Health Service as a research and development agency to complement the Occupational Safety and Health Administration. NIOSH has extensive laboratory capabilities and does a very thorough job of testing all types of respiratory protective equipment before it’s approved for use in the United States.

Unfortunately, however, the performance requirements for breathing apparatus have never specifically addressed the interior structural firefighting environment. Breathing apparatus that is approved by NIOSH and MSHA has been thoroughly tested and evaluated for an industrial and mining environment, but not for fire suppression.

The National Fire Protection Association adopted a standard for SCBA in 1981 and revised it extensively in 1987. While the first edition relied on the NIOSH/MSHA standards for performance requirements, the new edition of NFPA 1981 added performance requirements based on firefighting. One of the most important aspects of the new edition is a realistic flow rate to provide enough air for a hardworking firefighter without creating a negative pressure in the facepiece.

Highlights of NFPA 1981 – 1987 edition

The newest edition of NFPA 1981 applies new or additional requirements in the following areas:

• Increased air flow rates for heavy exertion.
• Stronger, more scratch-resistant lenses.
• Fire exposure test on straps and fabric components.
• Improved voice transmission through facepiece.
• Performance tested in hot and cold environments.
• Resistant to dust, corrosion, vibration and impact.

The new NFPA standard should be used for all new purchases of SCBA, and serious consideration should be given to upgrading or trading in older units that don’t meet the new standard.

Fire exposure tests

Among the new requirements in NFPA 1981 is a fire exposure test for the fabric components of an SCBA —the straps that carry the weight and hold the unit to the user’s body. There’s no direct fire exposure test for facepiece, tubes, hoses, or any other component.

The danger of melting or burning straps has been recognized for at least ten years, and some SCBA manufacturers introduced safer straps in advance of the new requirements. The new straps are made of fire-resistive materials. At least one manufacturer adds steel reinforcing to provide greater assurance that the SCBA will stay with the firefighter under the worst conditions.

Many of the older straps were made of materials that would melt or burn through at relatively low temperatures. Heat-resistant straps are now standard and are available as replacements on older SCBAs, but there have been no danger warnings and no product recalls from the manufacturers. The heat-resistant straps are offered as an upgrade option. In some cases, users have been reassured that the old straps are still acceptable and don’t have to be upgraded unless they’re worn out.

It has been suggested that the manufacturers are concerned that a legal judgment could force them to issue a recall and replace the straps at their expense. This would be an incentive for the manufacturers to settle liability claims for deaths or injuries that result from SCBA strap failure, rather than taking their chances in court.

In the meantime, thousands of firefighters are using SCBAs that may fall off their backs during a flashover. All of the straps susceptible to failure at low temperatures should be replaced as soon as possible.

The new edition of NFPA 1981 does not contain information on flame or high heat flux exposure of the facepiece or other apparatus components (other than fabric components). Requirements of this nature were proposed, but were dropped before the final draft was completed, presumably because there was no consensus on what the test should be or because none of the manufacturers were ready to have their units tested. The technical committee is working on such a test, but we will have to wait at least until the next edition of the standard to have a flame exposure test for the entire SCBA.

Investigations into firefighter deaths and several close calls indicate that components are failing in real fire exposures. When firefighters are found dead from smoke inhalation, with their facepieces still in place but with tubes burned through or with the lenses missing or cracked, we must suspect that SCBA failure may have been the direct cause of their deaths. Firefighters who barely escaped from flashovers have reported that their tubes burned through or their lenses failed just as they reached safety, while the rest of their equipment was undamaged. This strongly indicates that the SCBA is not as fire-resistive as we want it to be.

Maintenance

One of the excuses given for not using breathing apparatus is that you can’t count on them. Comments such as this one have come from firefighters who have reported that, in fairly routine circumstances, components of their SCBAs simply stopped working. Firefighters who died may have wanted to leave the same message. It’s evident that maintenance of SCBAs is lacking—almost nonexistent—in some fire departments.

The “drive it until it breaks and then fix it” mentality may be an option with automobiles, but it’s certainly not a valid approach to treating SCBAs. The middle of a burning, smoke-filled building is not the place to determine that your SCBA needs repairs. Every SCBA needs to be maintained on a regular basis by qualified technicians who can repair or replace components in the safety of a service facility. Do-it-yourself repairs should be absolutely prohibited, and maintenance records should be kept for every unit. The price for improper SCBA maintenance is simply too much to pay.

T t’s critical that we take a long, hard look at the breathing appaX ratus that firefighters strap on their backs—their design, maintenance, and use in fire situations. Old-style straps must be upgraded. Regular SCBA maintenance must be performed by qualified individuals, and serious consideration should be given to upgrading all existing SCBAs to meet the new NFPA standard. Finally, we must encourage SCBA manufacturers and the NFPA committee to make SCBA as fire-resistive as possible, so that it provides at least equal protection to the rest of the protective ensemble.