Out-of-Air Emergency: Using Technology to Survive


The fire service MUST embrace current technology to help reduce firefighter injuries and deaths. It’s about going home to your family and protecting your fellow firefighters. In every line-of-duty death (LODD), a member’s future plans have been cut short by a preventable accident or by inherent firefighting dangers that could have been mitigated (photo 1).

(1) A firefighter escapes an IDLH atmosphere. (Photo by Diane Gibson.)

Recent training and technological advances have shown promise in helping attain the goal of reducing the 100 LODDs that occur every year. A new “last chance” air-purifying respirator is a vital missing component to our current self-contained breathing apparatus (SCBA) ensemble. Note that it is a “component”—not a stand-alone device; it is to be used only in an emergency as the firefighter’s last chance for survival if he runs out of air.

Historically, firefighters equipped with a mask with a chest-mounted regulator and a low-pressure hose to the mask were trained to tuck the hose into their flannel-lined bunker coat if caught in an out-of-air situation. Although not effective for filtering out smoke toxins, it provided a crude air-purifying respirator. It also demonstrated firefighters’ awareness that an out-of-air emergency is a real possibility and that they should have a backup plan. Because of materials used in current building construction and furnishings, smoke is now more toxic than ever, thus heightening the need for a last-chance respirator.

The only other environment in which an out-of-air emergency occurs is that of scuba divers; many now carry pony bottles or emergency breathing devices for such emergencies. Since many fire departments have underwater rescue and recovery teams, why are divers—and not firefighters—equipped with emergency breathing devices when firefighters will find themselves in hostile environments more frequently? Carrying a five-minute escape SCBA is one possibility; but even if its weight negates its viability, how much time would this actually buy in a high-stress situation?

Although SCBA manufacturers take great pains to build reliable breathing apparatus, an out-of-air situation may result from work in a very hostile and dynamic fire environment. It is well documented that low-order failures as well as catastrophic ones can occur because of operator error or a manufacturer’s defect. A potential point of failure in some breathing apparatus is the high-pressure hose that connects the cylinder to the regulator. For whatever reason, if this should fail, the firefighter may find himself out of air in just a few minutes.

In 2005, according to the National Fire Protection Association, documented instances of smoke inhalation and respiratory distress accounted for 3,390 injuries in the U.S. fire service. In the 1990s, 63 percent of all nonheart attack deaths inside structure fires resulted from smoke inhalation. One study found that firefighters are just as likely to die in a structure fire today as they were 25 years ago. The rate of firefighter deaths in the 1990s was as high as three per 100,000 fires (Figure 1). Between 1995 and 2004, 79 firefighters died from smoke inhalation. Analysis of past LODDs shows the need for conservative air management training, safer staffing levels, and trained rapid intervention teams (RITs).

Figure 1. Causes of Firefighter Nonheart Attack Deaths
Source: Adapted from Rita F. Fahy, Ph.D., “U.S. Fire Service Fatalities in Structure Fires, 1977-2000.” National Fire Protection Association, July 2002. Used with permission.

However, even with the best training, the inherent dangers of firefighting demand that our members be given the best chance of surviving an out-of-air emergency. This technology does not take the place of implementing proper tactics training; it only complements it.

Past LODD data show that out-of-air emergencies result from several factors, including allowing insufficient time for exit, backpack entrapment, equipment malfunction, and disorientation (leading cause). We have all heard haunting tapes of radio calls for help from a lost firefighter who was running out of air. Whether in New Haven, Connecticut; Hackensack, New Jersey; Phoenix, Arizona; or New York City, no department is immune to this scenario.


The eighth item on the National Fallen Firefighter Foundation’s 16 Firefighter Life Safety Initiatives states, “Utilize available technology wherever it can produce higher levels of health and safety.” Essex PB&R Corporation has developed a filter canister, the Last Chance Rescue FilterSM, which is a one-time-use emergency backup respirator that attaches to the SCBA mask. The device has a service life of five years when maintained in its moisture-resistant barrier pouch. Models designed to fit specific manufacturers’ SCBA are available. The canister is lightweight (14.1 ounces), slightly larger than a soda can, and attaches to SCBA straps for easy access and increased accountability. The canister filters particulates as well as toxic fire gases such as hydrogen cyanide, acrolein, and hydrogen chloride and converts the most notable firefighter killer, carbon monoxide (CO), to nontoxic carbon dioxide. A review of 105 fire fatalities by Deputy Chief Ted Jarboe of Montgomery County, Maryland, found that soot and the gases listed above were found to be contributing factors in the death of all the victims.

How it works. Once the moisture-resistant barrier pouch has been torn open and the device is installed into the SCBA mask, the firefighter’s respiration draws contaminated air through the open end of the filter. The first stage of the filter is an N-95 pleated fiber filter that captures the visible (particulate) products of smoke and traps 95 percent of all particles 0.5 microns and larger. Autopsies show soot can carry toxins deep into the lungs and cause lower respiratory injuries, which this component mitigates.

Once the particulates above are removed, toxic gases enter the next stage of filtration, an activated carbon bed. Through the processes of adsorption and reaction, this stage removes most of the harmful gases, except for CO, which cannot be filtered.

The air containing CO passes through a granular bed of manganese dioxide/copper oxide (hopkalite) that converts this highly toxic gas to nontoxic carbon dioxide. The filtered and catalyzed air is then pulled up through the intake valve and into the SCBA face piece. The user exhales through the SCBA mask exhalation valves if applicable or back through the upper section of the emergency respirator and out its exhaust valves (photo 2).

(2) The Last Chance Rescue FilterSM. (Photo by Frank Ricci.)

The canister is rated to provide 15 minutes of breathable air for the firefighter in an out-of-air emergency. That is not 15 extra minutes to work and then exit. This, in conjunction with tracking, an integrated PASS device, an early call for help, and a trained RIT, could make the difference between a fatality and a close call.

It must be clearly understood that this is a last chance respirator for emergency use only. Currently, when a member is out of air, that person’s only choice is to breathe the ambient immediately dangerous to life and health (IDLH) atmosphere—not a good option! Using this technology will increase the chance for self-rescue and allow a RIT more time to locate the lost or trapped firefighter.

The International Association of Fire Chiefs has asked if use of this device would indicate a Mayday. The answer is no. The firefighter must call the Mayday as soon as he thinks he may be in trouble. There is no shame in calling for help if you get lost, separated, or low on air. All of these can occur long before your air tank is empty. The survival sequence is a large part of the Train the Trainer program that is posted for comment and peer review on FirefighterSafety.net. This site is linked to Fire Engineering’s, and we are linked back.


Then-Assistant Chief Steve Kreis of the Phoenix (AZ) Fire Department conducted more than 200 RIT drills, publishing his findings in “Rapid Intervention Isn’t Rapid” (Fire Engineering, December 2003). He found that the average time for entry was 2.55 minutes and an additional 5.33 minutes was needed to locate a downed member. The human body cannot survive without assistance in an IDLH environment. This article is very comprehensive and adds a lot to the dialogue on firefighter safety. Kreis acknowledges that these numbers are conservative, since fire, heat, and smoke were not present at the drills. With these conservative times in mind, operational changes, training, and technology must be pursued to provide the firefighter with the greatest chance for survival.

Investigative reports show that when a firefighter runs out of air, his first inclination is to rip off his mask, which would prevent the RIT from attaching an SCBA RIT pack to the mask on arrival. However, this canister attaches directly to the mask without removing gloves or helmet, allowing the RIT to easily attach an SCBA to the mask. In an extreme case of backpack entrapment, the firefighter may remove the entire assembly to aid in the escape from the structure, while keeping on the face piece (photo 3).


(3, 4) A firefighter with the canister in place. (Photo 3 by Kevin Reilly; photo 4 by Frank Ricci.)

Past firefighter fatalities have shown that the firefighter faced with an out-of-air emergency was either alone or with another firefighter in a similar situation. Let’s examine these scenarios: Two firefighters become lost, trapped, or disoriented within a fire building and are faced with an out-of-air emergency. What would they do? If equipped with buddy-breathing devices, it is likely that their air supply is about the same, so if they are experiencing an out-of-air crisis, what good is buddy breathing? The two firefighters can’t share air that neither one has. If the firefighter is alone and becomes lost, trapped, or disoriented and has an out-of-air emergency, buddy breathing and universal air connections are of no use. All he can do is attempt to get out and activate his PASS alarm and hope he is located before it is too late.

By equipping the firefighter with a backup respirator that interfaces with his existing mask, that person now may have time to get out, effect his own rescue, or at least stay alive while the RIT musters. It has been shown that often departments are not as prepared for the RIT scenario as they may have thought. Also, if the RIT is allowed to conduct operations outside the fire building and has to be reassembled for a rescue, there may also be a delay.

Furthermore, the latest standards on breathing apparatus require a universal air connection (UAC), which allows a high-pressure fill connection to attach and fill a downed firefighter’s cylinder. This is only practical if RIT arrives before the firefighter is out of air. It will likely take years before all existing breathing apparatus are upgraded to this standard. Even with redundant low-air alarm indicators, heads-up displays, bells, whistles, and whatever other means are developed, firefighters will still, unfortunately, find themselves in out-of-air emergencies. This is inevitable and has proven to be so every year since firefighters started wearing breathing apparatus. Despite of all the safety technology built into this equipment, proper training is paramount.


In an emergency, circumstances will dictate action, so take protective measures first, such as closing the door to the fire room, moving away from any heat source, and not delaying the Mayday call. Announce the Mayday three times, then identify your company, your location or last known location, your name, air supply status, and your crew location. If this information is not given, the incident commander must request it. Follow your department’s Mayday protocol.

The exact situation will determine whether you should move to find an exit or stay put. Generally, if in a home, you should try to find a window; in a commercial structure, if in contact with the RIT sector officer, move until you find an area of refuge or a structural feature that you can describe. Most RITs agree that it is harder to find a moving target in a commercial structure.

Let’s examine the donning process. It is imperative to stay on supplied air if you haven’t been rescued or found your way out.

Donning begins when your low-air alarm stops sounding. For my particular SCBA, this means that there are 100 psi in the bottle; for me, that means I have about six to eight breaths left. At this point, remove the moisture-resistant foil barrier pouch containing the respirator from the outer packaging. Grasp the two balls and tear open the moisture-resistant barrier pouch and remove the unit from the packing. I have had the opportunity to do this twice; once in complete darkness with gloves on.

Line up the indicating/locking dogs on the side of the canister. When you run out of air, take a final breath in, remove your regulator, insert the canister, and lock it in. Then exhale; this will push any inhaled products of combustion back through the filter and exhalation valves.

Stay low to the ground and breath off the floor, where the oxygen will be most abundant and the air cooler. Exit the IDLH atmosphere immediately (photo 4).

A Last Chance training canister is available to ensure proficiency with donning and doffing. You can practice with a blacked-out mask. This canister also replicates the low-breathing resistance the firefighter experiences when using the Last Chance Rescue Filter; it is best described as the resistance you encounter when breathing through three dust masks. The Middlesex (CT) Regional Fire Academy and Emergency Training Solutions LLC have developed a comprehensive train-the-trainer program. This program stresses making this emergency device a part of the department’s respiratory protection plan to ensure accountability and that the canister is not used for an unintended purpose (photo 5).

(5) A firefighter meters the environment during a Yale Study. (Photo by Keith Muratori.)



Breathing apparatus was once viewed as something that caused a delay. Firefighters had to dismount the apparatus, remove the SCBA from a cabinet, and then don a heavy steel cylinder. Before SCBA became mandatory, many firefighters would not wear them at all, or else they walked in the fire building’s front door and dumped it once they were out of the chief’s view.

Breathing apparatus are now lighter and more reliable. I doubt any firefighter would question its value. PASS alarms were introduced years ago and were originally stand-alone devices. As with SCBA, the new technology was considered a nuisance but has since proven its value. Eventually a standard evolved, NFPA 1982, Standard on Personal Alert Safety Systems (PASS). This led to the development of a hybrid SCBA with an optional integrated PASS alarm. The relevance and value of this new “backup” respirator to firefighting is obvious; the fire service should seriously consider it. As with any innovative technology, if we disregard it at its inception, we cannot realize the benefits that come from years of development.

Do no harm. What risks are involved in using a filter-type respirator in low-oxygen-level situations? Our emergency medical training has taught us, “Do no harm.” This filter respirator technology follows that credo: If you run out of air and there is not enough oxygen in the room, you will suffer injury or death with or without the canister. No harm is done by donning the Last Chance. If there is enough oxygen present, the Last Chance will greatly increase your chance of survival.

If a firefighter is lost, you can also perform tactics to increase ventilation to the structure. Study data indicate that ventilation has a direct impact on the inside environmental conditions. When conducted properly, ventilation decreases fire spread, reduces the presence of toxic gases, and increases oxygen. Considering the alternative, I feel that technology that might allow you a last chance to see your family is worth investing in.

Oxygen availability. What about the availability of oxygen in a structural fire? A 2006 study conducted by Yale University and presented at the National Conference of Emergency Physicians in Florida found that in residential structure fires, CO poses a greater threat to life than oxygen deprivation or heat.

The most recent Yale study that is under review tested five fires—four in a residential building and one in a commercial structure. The oxygen level data were consistent with earlier studies: The lowest oxygen reading on the floor for the five fires was 19 percent, whereas the lowest reading at the ceiling was 8.7 percent.

Data collected from a 1978 Boston study by Gold et al. indicated that out of 72 structural fires, recorded oxygen levels dropped below 18 percent at only six fires; the lowest reading of 15.5 percent was recorded for just a fraction of a minute. Oxygen levels between 15 and 19 percent decrease your ability to work strenuously, and impair coordination.

Without breathing protection, smoke inhalation brings on cognitive dysfunction and drowsiness. Even in an oxygen-deficient atmosphere, reducing CO in the bloodstream improves survivability. Note that in all 72 fires examined in the Boston study, the Last Chance respirator would have aided in reducing injury and death.

But as described previously, even in an extreme (and statistically rare) case in which no oxygen is present, a firefighter who deploys the device poses no significant additional hazard to himself; in that situation, the firefighter would die whether or not it was used. If the firefighter keeps the face mask on, this alone may be a mitigating factor if the RIT arrives before the firefighter is clinically dead. One general fire service misconception is the misunderstanding of the medical finding “Death caused by asphyxiation.” This means that oxygen has been displaced in the body or that chemicals such as hydrogen cyanide (HCN) or CO are preventing the cells from using the oxygen in the air. It is not an indication of the ambient oxygen present in the environment.

Two recent studies by Yale School of Medicine are being submitted for publication. We have had an opportunity to use the Last Chance Rescue Filter at a Yale Study with firefighters from all around the country, and I wouldn’t go to work without one.


When current regulations were drafted, filter respirator technology as described in this article was not a viable option for an out-of-air emergency. The filter platform was engineered to the European standard (EN 403) for emergency escape smoke hoods. The United States currently has no such notable standard. The manufacturer and fire service professionals feel that it is imperative to seek approval in the U.S. from the Occupational Safety and Health Administration (OSHA) and have the National Institute for Occupational Safety and Health (NIOSH) and the NFPA develop a standard for canister-type emergency filter respirators that are to be used only in conjunction with SCBA in an out-of-air emergency. The NFPA technical committee has appointed a new task group to work on a new standard for firefighter respiratory emergency escape devices. David Bernzweig is chairing the group, which will look into the feasibility of such a device and begin working on a standard. The fire service needs to advocate for the development of this standard to include this type of technology. Research has shown that OSHA standards and interpretations have made firefighters’ lives its number one priority when based on sound science.

OSHA 1910.156(f) (1) (iii) states, “Approved self-contained breathing apparatus may be equipped with either a ‘buddy-breathing’ device or a quick disconnect valve, even if these devices are not certified by NIOSH.”

According to a June 20, 1997, OSHA Standard Interpretation Letter, “SCBA Cylinder Interchageability,” OSHA 1910.134(d)(1)(ii); 1910.156(f)(1)(iv); and 1910.120(q)(3)(x) on SCBA cylinder interchangeably do “permit the use of other manufacturers’ cylinders on SCBA when deemed necessary to meet the tasks at hand. OSHA’s concession to this practice is only intended to be granted in an emergency, lifesaving situation.” This action voids the NIOSH certification. Understand that most SCBA cylinders are not designed to be interchangeable.

This technology is supported by sound science. The Last Chance Rescue Filter meets the filter performance criteria of EN 403, the European smoke hood standard. AT Labs, a unit of Assay Technologies, has conducted and validated the gas testing in the United States (Figure 2). Recent medical field trials conducted by Yale School of Medicine that have included firefighters and chief officers from FDNY; LA City and LA County, CA; Dallas, Texas; Detroit, MI; Montgomery County, MD; Indianapolis, IN; Naugatuck, New Haven, and Hamden, CT, have proven to be successful.

Figure 2. Gas Testing Performance Results

When a firefighter is out of air, his only option is to use his lungs, which are not certified by NIOSH. Buddy breathing devices that may not have NIOSH certification benefit a member only if he is alive. OSHA needs to once again place firefighter lives first and act on this critical issue. OSHA is expected to issue an interpretation on this technology this year. OSHA has never fined or cited any department for using this technology. Essex PB&R Corporation is committed to seeking approvals to have NIOSH develop certification criteria and work with the NFPA to develop a standard on emergency filter backup respirators.

Overreliance. A false sense of security is always a concern with any new technology. But because the Last Chance Rescue Filter does not have its own oxygen supply and works only one time, common sense combined with proper training and protocol will prevent misuse. These products are also cost-prohibitive for firefighters to use to extend their air time. By itself, this device is not the sole answer to reducing firefighter fatalities resulting from out-of-air emergencies. It is just another tool in our cache and must be coupled with other existing technologies such as PASS, tracking, UAC and RIT fittings, and buddy breathing. We must also increase training in firefighter survival techniques such as mask confidence, emergency breathing techniques, and firefighter safety and survival evolutions. Note the concern of getting in too deep has been the same argument for every new advance from hoods to bunker gear.

Training is the most important element in preventing the firefighter from getting into an out-of-air crisis. However, we must embrace technology, operational changes, and survival training if we are going to make an impact on the 81,000 injuries and 100 LODDs that occur each year. Clearly, nothing beats supplied air for respiratory protection. But in an emergency when supplied air is not available, this filter respirator technology gives the firefighter a “last chance” at surviving or limiting injury from an out-of-air emergency by providing an option he otherwise would not have before breathing in an IDLH atmosphere.

Authors’ note: Thanks to Desmond Mayne, Eric George, Kevin Reilly, Mike Donavan, Robert Halton, John Ricci, Jay Woron, Jim Duffy, Sam DeBurra, and Joseph Molis for their assistance in preparing this article.


Fahy, Rita F. Ph.D, “U.S. Fire Service Fatalities in Structure Fires, 1977-2000,” National Fire Protection Association, July 2002.

Gold, Avram, William A. Burgess, Edward V. Clougherty, “Exposure of firefighters toxic air contaminants,” American Industrial Hygiene Association Journal, Vol. 39, Issue 7, July 1978, 534-539.

Jarboe, Theodore L., “An examination of toxicity hazards associated with the burning of materials commonly encountered by firefighters,” Paper submitted to the National Fire Academy, February 1995.

Kreis, Steve, “Rapid Intervention Isn’t Rapid,” Fire Engineering, December 2003, 56-66.

National Fallen Firefighters Foundation Web Site, “16 Firefighter Life Safety Initiatives,” www.everyonegoeshome.com/initiatives.html.

National Institute for Occupational Safety and Health (NIOSH) Web site, “Fire Fighter Fatality Investigation and Prevention Program, www.cdc.gov/niosh/fire/.

Occupational Health and Safety Administration (OSHA) Web site, “Standard Interpretations,” interpretive letter re standards applicable to buddy breathing, April 22, 1985; interpretive letter re standards applicable to SCBA cylinder interchangeability, June 20, 1997, www.osha.gov.

FRANK RICCI is the director of fire services for ConnectiCOSH. He is an adjunct instructor for the New Haven (CT) Fire Department, Emergency Training Solutions, and Middlesex County (CT) Fire School and an FDIC H.O.T. instructor and lecturer. He has been a subject matter consultant for Yale, FDNY, and various manufacturers. He is a contributing author to >Carbon Monoxide Poisoning (CRC Press, 2008). Ricci has worked on a heavy rescue unit covering Bethesda and Chevy Chase, Maryland, and was a “student live-in” at station 31 in Rockville, Maryland. He was a co-author of the Connecticut whistle blower law. He most recently developed for Fire Engineering the DVD Smoke Showing. His DVD Firefighter Survival Techniques/Prevention to Intervention is available through Fire Engineering Books and Videos.

MATT MARCARELLI is a lieutenant with the New Haven (CT) Fire Department, assigned to Squad 1. An adjunct instructor for the department, he is also an instructor with the Connecticut Fire Academy and with the Middlesex (CT) County Fire School. Marcarelli is a rescue team manager for the Connecticut Urban Search and Rescue Task Force (CT TF-1). He has an associate’s degree in fire technology and teaches crisis communications to 911 telecommunicators with Powerphone Inc.

No posts to display