ADMINISTRATIVE REPORT DATE: January 20, 1998 PUBLIC HEALTH SERVICE/CDC/NIOSH/DSR FACE 98-03
TO: Director, National Institute for Occupational Safety and Health
FROM: Division of Safety Research, NIOSH
SUBJECT: Two Fire Fighters Die of Smoke and Soot Inhalation in Residential Fire – Pennsylvania
On October 27, 1997, two male fire fighters died of smoke and soot inhalation while fighting a residential fire. An Engine Company comprised of four fighters was responding to a 911 call of a downed power line in a residential neighborhood when one of the fire fighters noticed smoke emitting from the basement area of a nearby residence. Without notifying fire dispatch of the change in conditions (smoke coming from the residence), three fire fighters entered the residence to assist the residents out, and to survey the conditions and location of the fire. The fire fighters then exited the residence to don their self-contained breathing apparatus. Two of the fire fighters reentered the residence with a charged 3/4-inch booster line and proceeded to the basement (location of the fire) to attack the fire. This was the last time either fire fighter was seen alive. NIOSH investigators concluded that, to prevent similar occurrences, fire departments should:
! ensure that fire fighters advise dispatch of any change in conditions that would warrant a change in the status of unit(s) responding to a specific condition
! ensure that fire fighters wear and use PASS devices when involved in fire fighting, rescue, and other hazardous duties.
On October 27, 1997, two male fire fighters, victims #1 and #2, ages 43- and 27-years respectively entered the right side of a twin dwelling (the left side was not occupied) that had smoke emitting from the basement window. The two fire fighters entered the dwelling through the front door went in to the living room, then the breakfast room, and down the stairs to the basement. Approximately 30 minutes later, both fire fighters were found in the breakfast room, unresponsive. On October 29, 1997, the International Association of Fire Fighters (IAFF) requested that NIOSH provide technical assistance in reviewing the circumstances surrounding these fatalities. On November 24, 1997, the Chief, Trauma Investigations Section and a Safety Specialist conducted an investigation of this incident. Meetings were conducted with the Fire Commissioner and his staff, fire fighters responding to the incident, and the IAFF union representative and attorney for the union. Copies of photographs of the incident site were obtained from the fire department along with an estimated timeline of the incident, and a site
visit was conducted. The fire department involved in the incident serves a population of 1.4 million in a geographic area of 129 square miles. The fire department is comprised of 2,515 employees, of whom 2,387 are fire fighters. The fire department provides all new fire fighters with a 71-day training program at their fire academy which is designed to cover all areas of fire department operations, including tools and equipment, ladder operations, engine company operations, chemistry of fire, flashover, backdraft, use of respirators, hoseline operations, search and rescue, emergency medical training, and facility maintenance. The fire department’s written standard operating procedures manual was reviewed and appeared to be complete. The victims had 21 years fire fighting experience and 6 months experience, respectively.
On October 10, 1997, Engine Company 63 (a Lieutenant and 3 fire fighters) was dispatched at 0028 hours in response to a 911 call regarding a downed power line in a residential neighborhood. They arrived on the scene at 0032 hours and proceeded to rope off the area of the downed power line with barrier tape, and called the power company to report the downed line. One of the fire fighters was using a booster line (3/4-inch) to put out small fires started by the arcing power line. At approximately 0056 hours, the driver of Engine 63 noticed haze smoke emitting from the basement window of the residence that was affected by the downed power line. It was later determined that the broken neutral conductor from the power line had caused an electrical outlet in the dining room of the residence to short circuit. Burning embers from the short circuit fell through the floor into the basement via an opening for electrical conduit, igniting combustible materials in the basement. The owner of the residence was outside when the Lieutenant and two fire fighters went to investigate. The owner’s son was upstairs and was led out of the house by one of the fire fighters. The Lieutenant (victim #1) and one fire fighter (victim #2), using flashlights, proceeded through the light haze visible in the living room into the dining room and breakfast room, and down the stairs to the basement to evaluate the situation (figure), then retreated from the basement to the outside to don their self-contained breathing apparatus (SCBA).
At approximately 0107 hours victims #1 and #2 reentered the residence wearing SCBAs. They pulled in a 3/4-inch booster line and proceeded to the basement to attack the fire. At approximately 0117 hours, fire fighter #3, who was feeding line to #1 and #2, returned to the Engine to pull a 1 3/4-inch line, and to assist the driver in pulling a 3-inch line approximately 300 feet to a hydrant. The driver asked him what was going on in the residence. Fire fighter #3 stated he did not know. Fire fighter #3 then went back into the residence with a charged 1 3/4- inch line and advanced it as far as the dining room before encountering moderate smoke and poor visibility.
At 0122 hours, the driver of Engine 63, who remained on the outside to provide a hydrant hook- up and operate the pump, requested a Tactical Box, which consists of one additional pumper (Lieutenant and 3 fire fighters), 2 Ladder Trucks (each with one Lieutenant and 4 fire fighters), and one Battalion Chief and aide. This was the first time fire dispatch was alerted as to a possible fire at the residence near the downed power line.
At 0125 hours the Battalion Chief arrived on the scene and attempted to call Engine 63 on the portable radio, but received no response. At approximately the same time, Engine 51, Ladder 29, and Ladder 8 arrived on the scene. Two fire fighters from Ladder 29 remained on the exterior of the house to perform ventilation while the Lieutenant and two fire fighters from Ladder 29 went into the residence to perform a routine primary search. The first fire fighter to enter followed the 1-3/4 inch line where he located fire fighter #3 from Engine 63. The Lieutenant from Ladder 29 also reached fire fighter #3 and asked him, “Where is your Company?” Fire fighter #3 stated that he could not find his company, but he thought they were in the basement. The Lieutenant stated that at this time visibility was very poor. One of the fire fighters from Ladder 29 proceeded upstairs to break out windows to help vent the residence. The Lieutenant and a fire fighter from Ladder 29, and fire fighter #3 from Engine 63, exited the residence. The fire fighter from Ladder 29, who was upstairs venting the residence, returned to the downstairs dining room where he found the nozzle of the 1 3/4-inch charged line and saw the booster line going down the steps to the basement. He then decided to return to the second floor, following the 1 3/4-inch line, and ran into the Battalion Chief in the living room. The Battalion Chief then radioed on the fireground band to look for the missing fire fighters from Engine 63.
At 0142 hours a Full Box was requested, which consists of two more Engines plus another Battalion Chief. Also, at this time Ladder 29 fire fighters were entering the residence from the front, and Engine 51 fire fighters were entering the basement from the rear of the residence.
During this time, two fire fighters from Ladder 29 entered the front door and proceeded into the breakfast room where they found both fire fighters from Engine 63 in a kneeling/crouched position, mask off, and unresponsive. Both downed fire fighters, still unresponsive, were removed from the residence. They were transported by EMS to a local hospital where advanced life support failed to revive either fire fighter.
Since both fire fighters were found with their masks off, it can be inferred that they had run out of air and no one heard the low-air alarms. Neither fire fighter had turned on their personal alert safety systems (PASS) devices.
Note: Both SCBA’s worn by the victims were sent to the NIOSH Certification and Quality Assurance Branch for testing. A copy of the NIOSH evaluation of the SCBA’s is included as an Appendix to this report.
CAUSE OF DEATH: According to the medical examiner, the cause of death was due to smoke and soot inhalation. Carboxyhemoglobin levels were 38% and 63%, respectively.
Recommendation #1: Fire departments should ensure that fire fighters advise dispatch on any change of conditions that would warrant a change in the status of unit(s) responding to a specific condition.
Discussion: One engine was dispatched on a notice of a downed power line. However, during this routine nonfire response, conditions at the scene of the downed power line changed when one of the fire fighters noticed smoke coming from the basement window of the residence affected by the downed line. An investigation into the smoke coming from the residence was
initiated without notifying dispatch of a change in conditions. Had dispatch been alerted to smoke from the residence, additional support would have immediately been dispatched to the incident scene.
Recommendation # 2: Fire departments should strictly enforce the wearing and use of PASS devices when fire fighters are involved in fire fighting, rescue, and other hazardous duties.
Discussion: The PASS device is a small electrical device worn by the fire fighter which will emit a distinctive audible alarm if the fire fighter becomes motionless for more than 30 seconds. Both fire fighter victims were wearing PASS devices; however, neither device had been activated.
National Fire Protection Association. NFPA 1500, Standard on Fire Department Occupatiohnal Safety and Health Program, National Fire Protection Association, Quincy, MA.
Ted A. Pettit, M.S., R.E.H.S. Richard W. Braddee Chief Project Officer Trauma Investigations Section Trauma Investigations Section Surveillance and Field Surveillance and Field
Investigations Branch Investigations Branch Division of Safety Research Division of Safety Research
Thomas K. Hodous, M.D. Acting Chief Surveillance and Field
Investigations Branch Division of Safety Research
Fire Fighter Fatality Project – Using the Fatality Assessment and Control Evaluation (FACE) Project
The National Institute for Occupational Safety and Health (NIOSH), Division of Safety Research (DSR), performs Fatality Assessment and Control Evaluation (FACE) investigations when a line-of-duty Fire Fighter Fatality is reported. The goal of these evaluations is to prevent fatal work injuries in the future by studying the working environment, the worker, the task the worker was performing, the tools the worker was using, the energy exchange resulting in fatal injury, and the role of management in controlling how these factors interact.
Division of Safety Research National Institute for Occupational
Safety and Health (NIOSH) 1095 Willowdale Road
Morgantown, West Virginia 26505-2888 Phone: (304) 285-5916
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FIR 2303, Fire Behavior and Combustion 1
Course Learning Outcomes for Unit VI Upon completion of this unit, students should be able to:
2. Categorize the components of fire. 2.1 Restate the two main types of smoke aerosols.
4. Describe the process of burning.
4.1 Demonstrate the principal combustion products formed in fires. 4.2 Explain how soot forms.
Course/Unit Learning Outcomes
2.1 Unit Lesson Chapter 10, pp. 175–194 Unit VI Essay
4.1 Unit Lesson Chapter 10, pp. 175–194 Unit VI Essay
4.2 Unit Lesson Chapter 10, pp. 175–194 Unit VI Essay
Required Unit Resources Chapter 10: Combustion Products, pp. 175–194 In order to access the following resource, click the link below. Pandey, P., & Pundir, B. P. (2015). Role of fluid-dynamics in soot formation and microstructure in acetylene-
air laminar diffusion flames. International Journal of Spray and Combustion Dynamics, 7(1), 25–38. https://journals.sagepub.com/doi/pdf/10.1260/1756-82126.96.36.199
Unit Lesson Recap In the previous unit, we covered pyrolysis of solids forming gaseous fragments suspended in the thermal plume as soot. Pyrolysis of solids undergoes chemical changes, and once the flaming is independent of the ignition source, the burning rate is dependent on the radiant heat preheating combustibles. The speed, magnitude, and direction of flame spread is affected by the airflow and the availability of oxygen-rich air. Combustion Products and Smoke Many movies and TV series show firefighters crawling down high-rise corridors or into rooms on fire with raging flames splitting their helmets or flames skipping across the ceiling. The flames glow orange-yellow as they dance across the ceiling, and there is no visible smoke. In the TV series Chicago Fire , many scenes show the actor’s face without wearing a self-contained breathing apparatus (SCBA) face mask and many times wearing oversized SCBA face masks in heavy fire conditions without any smoke or by-products visible (Gilvary & Dale, 2014). Where is the smoke? In previous units, we learned that incandescent orange-yellow
UNIT VI STUDY GUIDE
Various Materials and Their Relationship to Fire as Fuelhttps://journals.sagepub.com/doi/pdf/10.1260/1756-82188.8.131.52
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flaming produces smoke or fire effluents. Even though it is a television show, are we teaching the wrong information regarding combustion products? Is oversimplification of these scenes dangerous? Fire Smoke Several decades ago, many firefighters were proud to be known as smoke eaters. Firefighters willingly entered the lethal smoke to search for victims gasping for breaths of air whenever possible, using rags or even beards to try and filter the smoke. In more recent times, smoke eaters are seasoned firefighters that earned the title as a rite of passage, wearing their badge of courage of soot around their nose and mouth with hoarse voices. This was the era of wearing long bunker coats, ¾ boots with no SCBA; or if you had SCBAs on the apparatus, you were told they were only for real emergencies. In a typical structure fire, it was believed that the smoke contained particulates consisting of wood, wool, and paper burning, and it was not realized how lethal the smoke was. Today we understand the gasification of fuel and the combustion rate of carbonaceous solid particles and aerosol mist in smoke are extremely toxic and flammable. At present, smoke from a residential structure fire may contain fragments from plastics, foams, fabrics, carpets, wood products, and synthetic materials. Each of these materials undergoes pyrolysis in a fire and become deposited in the smoke. Nonetheless, exposures to any of these products result in respiratory hazards. As a result, many fire departments developed air management policies and procedures for wearing SCBAs. The trend today is to require firefighter air replenishment systems (FARS) installed in large area buildings, high rises, as well as other areas considered difficult to replenish air for firefighter safety. General Nature of Smoke The general makeup of smoke is carbonaceous solid particles and aerosol mist (Gann & Friedman, 2015). Several authors suggest soot is the result of unburned carbon particles from incomplete combustion resulting in aggregates of soot (Gorbett & Pharr, 2011; Köylü, & Faeth, 1994; Köylü et al., 1995). Gann and Friedman (2015) described turbulent fires as producing large soot particles that stick to other particles forming larger aggregates called coagulation, which is dangerous and extremely flammable. What causes these larger aggregates of smoke? As seen previously, diffusion flames are seen as less-localized and tend to burn slower, producing more soot as oxygen is diffused into the flames. This can be seen in fires where synthetic material, such as in a chair, burns and then self-extinguishes leaving large amounts of black soot adhered to the walls and ceiling above the neutral plane. Radiative heat from the soot in flames and the gasification of the synthetic material caused visual obscuration known as aerosols (Gann & Friedman, 2015). These same aerosols are what residential smoke detectors detect during a fire. Smoke is mainly gaseous products made up of H2O and CO2. In addition, when incomplete combustion occurs, CO and other organic molecules are generated (Figure 1). Smoke Color
On the fire ground, when descriptions of the smoke color are given, it paints a picture for all incoming units to know if there is a working fire (Figure 2). However, many company officers have different definitions on the color of smoke. For some company officers, light-colored smoke is dark and others dark-colored smoke is light. This is based many times on the experience of the company officer. Nonetheless, we know that carbonaceous solid particles that generate the incandescent orange-yellow flame have black smoke originating from the flame (Gann & Friedman, 2015). Light-colored smoke is aerosol mist that cools and condenses and is normally
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seen in the early stages of flaming or when being extinguished. In addition, well-ventilated to under-ventilated conditions affect the color of smoke. Low-volume, light-colored smoke that is slow moving may be the beginning stage of a fire or it could be a well-developed fire where the thermal column is starting to cool. Light-colored smoke could even be carbonaceous solid particles producing black smoke; however, if it is a dark rainy day the smoke looks light as compared to the background color of the storm. For decades, many fire instructors taught that smoke color indicates what is burning. Maybe that is correct if items burning were isolated. In legacy and modern fires, there are multiple items burning made from multiple chemical products producing different particulates that continuously combine with other particulates changing the color of the smoke. Soot Formation Soot is a complex mixture of different gases and particulates resulting from incomplete combustion producing mainly carbon and hydrogen. The soot formation process occurs with diffusion and fuel-rich premixed flames when under-ventilated burning occurs (Gann & Friedman, 2015). This process is also affected by the amount of moisture or humidity in the air. Moisture or humidity in the air affects the temperature of thermal fragmentation of fuel molecules producing soot residue that can adhere to walls and the ceiling. As firefighters, you may have been in a fire where the soot is almost sticky in nature and adheres to your face mask and bunker gear. If you recall, most likely this fire was a smoldering fire where temperatures were not extreme. Soot from oxygen-rich fires burns very fast with high temperatures and leaves less residue. Soot particulate matter diameters range from 0.01 to 1 µm in size (Gann & Friedman, 2015). Items that are statically charged will also cause soot to adhere to it more readily than matter that is not electrostatically charged. During the flaming process, soot particles collide and merge to form larger molecules and deposit on the surfaces from the neutral plane up. However, some particles unite with other particles growing larger in size until the mass is large enough that gravity causes the soot to fall below the neutral plane. Gann and Friedman (2015) describe coagulation as the bond of particles to form larger particles and the more turbulent the flaming, the larger the particle. In addition, fuels with hydrogen carbon ratios higher than saturated hydrocarbons produce sootier flames. Optical Density Many times, firefighters experience the obscuration of a light beam traveling through the smoke as they crawl through a structure. The visibility reduction of the light beam in smoke is dependent on ventilation and the particles of incomplete combustion (Figure 3). Smoke is laden with droplets of condensation from fire gases and soot particles making visibility difficult even in small fires (Gorbett & Pharr, 2015). A pot on the stove with fewer smoke particles allows the light beam to pass through the smoke due to less light absorption. However, dense, thick, black smoke reduces visibility because only a fraction of the light can pass through due to light absorption (Ingason & Persson, 2006). Points to Ponder In the scenario below, do the smoke aerosols present risk to the firefighters? Why did the smoke conditions change from being able to cut the particles and aerosols with light to being completely obscured? Was it the fire-generated soot and aerosols that reduced the visibility? Does the heavy soot exceed the tenability limit of the firefighters?
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Conclusion Smoke or fire effluent is sometimes black and sometimes white in appearance, depending on the aerosols and gases. Soot is mainly carbon particles from under-ventilated flaming. In the flame, carbonaceous solid particles produce the incandescent orange-yellow glow and black smoke emanating from the flame. Both soot and smoke reduce the ability of firefighters to be able to see in a fire. Smoke conditions can change radically as the fire consumes more and more combustible materials, producing gaseous products of H2O and CO2. Incomplete combustion generates CO, as well as other organic molecules.
References Gann, R. G., & Friedman, R. (2015). Principles of fire behavior and combustion (4th ed.). Jones & Bartlett
Learning. Gilvary, M. (Writer), & Dale, H. (Director). (2014, March 4). Keep your mouth shut (Season 2, Episode 15) [TV
series episode]. In D. Wolf (Executive Producer). Chicago Fire. Wolf Films, Universal Television. Gorbett, G. E., & Pharr, J. L. (2011). Fire dynamics. Pearson. Ingason, H., & Persson, B. (2006). Prediction of optical density using CFD. Fire Safety Science—Proceedings
of the Sixth International Symposium, 817–828. http://iafss.org/publications/fss/6/817/view/fss_6- 817.pdf
Köylü, Ü. Ö., & Faeth, G. M. (1994). Optical properties of soot in buoyant laminar diffusion flames. Journal of
Heat Transfer, 116(4), 971–979. Köylü, Ü. Ӧ., Faeth, G. M., Farias, T. L., & Carvalho, M. G. (1995). Fractal and projected structure properties
of soot aggregates. Combustion and Flame, 100(4), 621–633. https://www.sciencedirect.com/science/article/abs/pii/001021809400147K
Building on the Scenario Engine 12 (second alarm) made entrance to the stairwell from Side “A” and began to push towards the area of the fire pulling a 1 ¾” handline. They noticed the stairwell was smoke-logged. At first, they were able to cut through the smoke with just flashlights and the nearby exit sign on the second floor was still visible. As they pushed deeper down the hallway, the light was cutting the smoke less and less. Finally, the dark smoke was completely concealing everything, making it more and more difficult to search with the flashlights only penetrating a few inches. The soot particles in the air seemed to soak up every ounce of the light as they bumped into Tower 2 dragging the unresponsive firefighter from Engine 5 down the hallway away from the fire. Engine 12 continued towards the fire, noting the conditions were changing radically and the tenability was taking a toll on them. Engine 12’s crew became disorientated from the dense black smoke and heat.
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Suggested Unit Resources In order to access the following resource, click the link below. In the video, you will see aerosol droplets resulting from condensation of gases that are beginning to cool as they leave the vicinity of the flames inside of the container. However, as seen in the video, the aerosol droplets will ignite when the fire is placed in the right mixture as it is leaving the container. There are two main types of smoke aerosols distinguished by the color of the smoke. This is fire footage with no narration, so no transcript is needed. VentEnterSearch. (2011, April 30). Smoke combustion [Video]. YouTube.
Learning Activities (Nongraded) Nongraded Learning Activities are provided to aid students in their course of study. You do not have to submit them. If you have questions, contact your instructor for further guidance and information.
For this activity, you are asked to prepare flash cards. Our textbook suggests that both soot and aerosols reduce the ability to see in a fire. Smoke is sometimes black and sometimes white in appearance. Using the PowerPoint presentation linked here, explain what each concept/term means in one or two sentences on back of the flash card. You may use various sources, including your textbook or other scholarly material; however, the point of flash cards is for you to actively and skillfully conceptualize, apply, analyze, and evaluate the differences in soot and aerosols from what you have you experienced in live fires and read in this lesson. What has been your observation, experience, reflection, or reasoning for the differences in color? Is there a difference? Why, or why not? This is an opportunity for you to express your thoughts about the material you are studying by writing about it. Conceptual thinking is a great way to study because it gives you a chance to process what you have learned and increases your ability to remember it. If you have any questions or do not understand a concept, contact your professor for clarification.https://www.youtube.com/watch?v=OxnxhewgFL8https://online.columbiasouthern.edu/bbcswebdav/xid-120240829_1
For this assignment, you will complete the sixth essay of the scenario-based case study. The essay should be a two-page narrative focusing on arguments that support what the authors discuss in Chapter 10, as well as other research that you conduct related to these concepts.
The questions below may help you to focus your essay on the one or two concepts chosen :
· Were there any factors that influenced the smoke or fire effluent occurrence of the extreme fire behavior phenomenon?
· Did extreme fire behavior involve aerosols (soot particles and liquid droplets) and gases? If so, what type of event happened?
· Were there any effects of the under-ventilated burning?
· Did aerosol droplets from the condensation of gases affect fire attack or rescue efforts?
· Did the radiative transfer from the soot, flames, and hot upper layers in the fire room affect the rate at which the fuel burns and the likelihood of ignition? Did this affect fire attack or rescue efforts?
· What impact did the soot and aerosols have on the ability to see in a fire?
· What effect did the smoke obscuration have on fire attack or even rescue efforts?
Use APA guidelines and summarize your response. To supplement your discussion and support your conclusions, you should use information from the CSU Online Library from reputable, reliable sources, such as journal articles, case studies, scholarly papers, and other sources that you feel are pertinent. All sources used, including the textbook, must be referenced; paraphrased and quoted material must have accompanying citations following APA guidelines. You must include at least three sources, including your textbook.
This assignment must be submitted and graded by the professor, who will provide feedback to you. Your assignment will be graded according to the assigned rubric. The professor will grade and annotate items that need to be corrected for your final project. This feedback from the professor will help you correct any discrepancies before including this assignment in the final project. In addition, implementing the feedback will help you submit a quality project and achieve an overall better review and grade.