Posts Tagged ‘fire investigation’

Townhouse Fire: Washington, DC:
Computer Modeling

Monday, September 28th, 2009

This post continues study of an incident in a townhouse style apartment building in Washington, DC with examination of the extreme fire behavior that took the lives of Firefighters Anthony Phillips and Louis Mathews.

A Quick Review

Prior posts in this series, Fire Behavior Case Study of a Townhouse Fire: Washington, DC, Townhouse Fire: Washington, DC-What Happened,and Townhouse Fire: Washington, DC-Extreme Fire Behavior examined the building and initial tactical operations at this incident. The fire occurred in the basement of a two-story, middle of building, townhouse apartment with a daylight basement. This configuration provided at grade entrances to Floor 1 on Side A and the Basement on Side C.

Engine 26, the first arriving unit reported heavy smoke showing from Side A and observed a bi-directional air track at the open front door. Engines 26 and 10 operating from Side A deployed hoselines into the first floor to locate the fire. Engine 17, the second due engine, was stretching a hoseline to Side C, but had insufficient hose and needed to extend their line. Truck 4, the second due truck, operating from Side C opened a sliding glass door to the basement to conduct search and access the upper floors (prior to Engine 17’s line being in position). When the door on Side C was opened, Truck 4 observed a strong inward air track. As Engine 17 reached Side C (shortly after Rescue 1 and a member of Truck 4 entered the basement) and asked for their line to be charged. Engine 17 advised Command that the fire was small.

Conditions changed quickly after the door on Side C was opened, as conditions in the basement rapidly transitioned to a fully developed fire with hot gases and flames extending up the interior stairway trapping Firefighters Phillips, Mathews, and Morgan. Confusion about building configuration (particularly the number of floors and location of entry points on Side A and C) delayed fire attack due to concern for opposing hoselines.

Modeling of the Cherry Road Incident

National Institute for Standards and Technology (NIST) performed a computer model of fire dynamics in the fire at 3146 Cherry Road (Madrzykowski and Vettori, 2000) using the NIST Fire Dynamics Simulator (FDS) software. This is one of the first cases where FDS was used in forensic fire scene reconstruction.

Fire Modeling

Fire modeling is a useful tool in research, engineering, fire investigation, and learning about fire dynamics. However, effective use of this tool and the information it provides requires understanding of its capabilities and limitations.

Models, such as the National Institute of Standards and Technology (NIST) Fire Dynamics Simulator (FDS) relay on computational fluid dynamics (CFD). CFD models define the fire environment by dividing it into small, rectangular cells. The model simultaneously solves mathematical equations for combustion, heat transfer, and mass transport within and between cells. When used with a graphical interface such as NIST Smokeview, output can be displayed in a three-dimensional (3D) visual format.

Models must be validated to determine how closely they match reality. In large part this requires comparison of model output to full scale fire tests under controlled conditions. When used for forensic fire scene reconstruction, it may not be feasible to recreate the fire to test the model. In these situations, model output is compared to physical evidence and interview data to determine how closely key aspects of model output matched events as they occurred. If model output reasonably matches events as they occurred, it is likely to be useful in understanding the fire dynamics involved in the incident.

It is crucial to bear in mind that fire models do not provide a reconstruction of the reality of an event. They are simplified representation of reality that will always suffer from a certain lack of accuracy and precision. Under the condition that the user is fully aware of this status and has an extensive knowledge of the principles of the models, their functioning, their limitations and the significance attributed to their results, fire modeling becomes a very powerful tool (Dele“mont & Martin, J., 2007, p. 134).

FDS output included data on heat release rate, temperature, oxygen concentration, and velocity of gas (smoke and air) movement within the townhouse. As indicated above, model output is an approximation of actual incident conditions.

In large scale fire tests (McGrattan, Hamins, & Stroup, 1998, as cited in Madrzykowski and Vettori, 2000), FDS temperature predictions were found to be within 15% of the measured temperatures and FDS heat release rates were predicted to within 20% of the measured values. For relatively simple fire driven flows such as buoyant plumes and flows through doorways, FDS predictions are within experimental uncertancies (McGrattan, Baum, & Rehm, 1998, as cited in Madrzykowski and Vettori, 2000).

Results presented in the NIST report on the fire at 3146 Cherry Road were presented as ranges to account for potential variation between model output and actual incident conditions.

Heat release rate is dependent on the characteristics and configuration of the fuel packages involved and available oxygen. In a compartment fire, available oxygen is dependent on the ventilation profile (i.e., size and location of compartment openings). The ventilation profile can change over time due to the effects of the fire (e.g., failure of window glazing) as well as human action (i.e., doors left open by exiting occupants, tactical ventilation, and tactical anti-ventilation)

In this incident there were a number of changes to the ventilation profile. Most significant of which were, 1) the occupant opened the second floor windows on Side C (see Figure 3), 2) the occupant left the front door open as they exited (see Figures 1 &2 ), 3) tactical ventilation of the first floor window on Side A, and opening of the sliding glass door in the basement on Side C (see Figures 1-3). In addition, the open door in the basement stairwell and open stairwell between the Floors 1 and 2 also influenced the ventilation profile (see Figure 1).

Figure 1. Cross Section of 3146 Cherry Road NE

cherry_road_cross_section

Figure 2. Side A 3146 Cherry Road NE

side_a_post_fire

Figure 3. Side C 3146 Cherry Road NE

side_c_post_fire

Figure 4 illustrates the timing of changes to the ventilation profile and resulting influence on heat release rate in modeling this incident. A small fire with a specific heat release rate (HRR) was used to start fire growth in the FDS simulation. In the actual incident it may have taken hours for the fire to develop flaming combustion and progression into the growth stage. Direct comparison between the simulation and incident conditions began at 100 seconds into the simulation which corresponds to approximately 00:25 during the incident.

Figure 4. FDS Heat Release Rate Curve

cherry_road_hrr_curve

Note: Adapted from Simulation of the Dynamics of the Fire at 3146 Cherry Road NE Washington D.C., May 30, 1999, NISTR 6510 (p. 14) by Dan Madrzykowski and Robert Vettori, 2000, Gaithersburg, MD: National Institute for Standards and Technology.

Questions

The following questions are based on heat release rate data from the FDS model presented in Figure 4.

  1. What was the relationship between changes in ventilation profile and heat release rate?
  2. What would explain the rapid increase in heat release rate after the right side of the basement sliding glass door is opened?
  3. Why might the heat release rate have dropped slightly prior to opening of the left side of the basement sliding glass door?
  4. Why did the heat release rate again increase rapidly to in excess of 10 MW after the left side of the basement sliding glass door was opened?
  5. How does data from the FDS model correlate to the narrative description of events presented in prior posts about this incident (Fire Behavior Case Study of a Townhouse Fire: Washington, DC, Townhouse Fire: Washington, DC-What Happened,and Townhouse Fire: Washington, DC-Extreme Fire Behavior)?

More to Follow

In addition to heat release rate data the computer modeling of this incident provided data on temperature, oxygen concentration, and gas velocity. Visual presentation of this data provides a more detailed look at potential conditions inside the townhouse during the fire. The next post in this series will present and examine graphic output from Smokeview to aid in understanding the fire dynamics and thermal environment encountered during this incident.

Master Your Craft

Ed Hartin, MS, EFO, MIFireE, CFO

References

District of Columbia (DC) Fire & EMS. (2000). Report from the reconstruction committee: Fire at 3146 Cherry Road NE, Washington DC, May 30, 1999. Washington, DC: Author.

Madrzykowski, D. & Vettori, R. (2000). Simulation of the Dynamics of the Fire at 3146 Cherry Road NE Washington D.C., May 30, 1999, NISTR 6510. August 31, 2009 from http://fire.nist.gov/CDPUBS/NISTIR_6510/6510c.pdf

National Institute for Occupational Safety and Health (NIOSH). (1999). Death in the line of duty, Report 99-21. Retrieved August 31, 2009 from http://www.cdc.gov/niosh/fire/reports/face9921.html

Townhouse Fire: Washington, DC
What Happened

Monday, September 14th, 2009

This post continues study of an incident that resulted in two line-of-duty deaths as a result of extreme fire behavior in a townhouse style apartment building in Washington, DC.

A Quick Review

The previous post in this series, Fire Behavior Case Study of a Townhouse Fire: Washington, DC examined building construction and configuration that had a significant impact on the outcome of this incident. The fire occurred in the basement of a two-story, middle of building, townhouse style apartment with a daylight basement. This configuration provided an at grade entrance to the Floor 1 on Side A and an at grade entrance to the Basement on Side C.

The fire originated in an electrical junction box attached to a fluorescent light fixture in the basement ceiling (see Figures 1 and 2). The occupants of the unit were awakened by a smoke detector. The female occupant noticed smoke coming from the floor vents on Floor 2. She proceeded downstairs and opened the front door and then proceeded down the first floor hallway towards Side C, but encountered thick smoke and high temperature. The female and male occupants exited the structure, leaving the front door open, and made contact with the occupant of an adjacent unit who notified the DC Fire & EMS Department at 0017 hours.

Dispatch Information

At 00:17, DC Fire & EMS Communications Division dispatched a first alarm assignment consisting of Engines 26, 17, 10, 12, Trucks 15, 4, Rescue Squad 1, and Battalion 1 to 3150 Cherry Road NE. At 0019 Communications received a second call, reporting a fire in the basement of 3146 Cherry Road NE. Communications transmitted the update with the change of address and report of smoke coming from the basement. However, only one of the responding companies (Engine 26) acknowledged the updated information.

Weather Conditions

Temperature was approximately 66o F (19o C) with south to southwest winds at 5-10 mi/hr (8-16 km/h), mostly clear with no precipitation.

Conditions on Arrival

Approaching the incident, Engine 26 observed smoke blowing across Bladensburg Road. Engine 26 arrived at a hydrant at the corner of Banneker Drive and Cherry Road at 00:22 hours and reported smoke showing. A short time later, Engine 26 provided an updated size-up with heavy smoke showing from Side A of a two story row house. Based on this report, Battalion 1 ordered a working fire dispatch and a special call for the Hazmat Unit at 00:23. This added Engine 14, Battalion 2, Medic 17 and EMS Supervisor, Air Unit, Duty Safety Officer, and Hazmat Unit.

Firefighting Operations

DC Fire and EMS Department standard operating procedures (SOP) specify apparatus placement and company assignments based on dispatch (anticipated arrival) order. Note that dispatch order (i.e., first due, second due) may de different than order of arrival if companies are delayed by traffic or are out of quarters.

Standard Operating Procedures

Operations from Side A

The first due engine lays a supply line to Side A, and in the case of basement fires, the first line is positioned to protect companies performing primary search on upper floors by placing a line to cover the interior stairway to the basement. The first due engine is backed up by the third due engine. The apparatus operator of the third due engine takes over the hydrant and pumps supply line(s) laid by the first due engine, while the crew advances a backup line to support protection of interior exposures and fire attack from Side A.

The first due truck takes a position on Side A and is responsible for utility control and placement of ladders for access, egress, and rescue on Side A. If not needed for rescue, the aerial is raised to the roof to provide access for ventilation.

The rescue squad positions on Side A (unless otherwise ordered by Command) and is assigned to primary search using two teams of two. One team searches the fire floor, the other searches above the fire floor. The apparatus operator assists by performing forcible entry, exterior ventilation, monitoring search progress, and providing emergency medical care as necessary.

Operations from Side C

The second due engine lays a supply line to the rear of the building (Side C), and in the case of basement fires, is assigned to fire attack if exterior access to the basement is available and if it is determined that the first and third due engines are in a tenable position on Floor 1. The second due engine is responsible for checking conditions in the basement, control of utilities (on Side C), and notifying Command of conditions on Side C. Command must verify that the first and third due engines can maintain tenable positions before directing the second due engine to attack basement fires from the exterior access on Side C.

The second due truck takes a position on Side C and is responsible for placement of ladders for access, egress, and rescue on Side C. The aerial is raised to the roof to provide secondary access for ventilation (unless other tasks take priority).

Command and Control

The battalion chief positions to have an unobstructed view of the incident (if possible) and uses his vehicle as the command post. On greater alarms, the command post is moved to the field command unit.

Notes: This summary of DC Fire & EMS standard operating procedures for structure fires is based on information provided in the reconstruction report and reflects procedures in place at the time of the incident. DC Fire & EMS did not use alpha designations for the sides of a building at the time of this incident. However, this approach is used here (and throughout the case) to provide consistency in terminology.

First due, Engine 26 laid a 3″ (76 mm) supply line from a hydrant at the intersection of Banneker Drive and Cherry Road NE, positioned in the parking lot on Side A, and advanced a 200′ 1-1/2″ ( 61 m 38 mm) pre-connected hoseline to the first floor doorway of the fire unit on Side A (see Figures 1 and 2). A bi-directional air track was evident at the door on Floor 1, Side A , with thick (optically dense) black smoke from the upper area of the open doorway. Engine 26’s entry was delayed due to a breathing apparatus facepiece malfunction. The crew of Engine 26 (Firefighters Mathews and Morgan and the Engine 26 Officer) made at approximately 00:24.

Figure 1. Plot and Floor Plan-3146 Cherry Road NE

plot_and_floor

Note: Adapted from Report from the Reconstruction Committee: Fire at 3146 Cherry Road NE, Washington DC, May 30, 1999, p. 18 & 20. District of Columbia Fire & EMS, 2000; Simulation of the Dynamics of the Fire at 3146 Cherry Road NE, Washington D.C., May 30, 1999, p. 12-13, by Daniel Madrzykowski & Robert Vettori, 2000. Gaithersburg, MD: National Institute of Standards and Technology, and NIOSH Death in the Line of Duty Report 99 F-21, 1999, p. 19.

Engine 10, the third due engine arrived shortly after Engine 26, took the hydrant at the intersection of Banneker Drive and Cherry Road, NE, and pumped Engine 26’s supply line. After Engine 10 arrived at the hydrant, the firefighter from Engine 26 who had remained at the hydrant proceeded to the fire unit and rejoined his crew. Engine 10, advanced a 400′ 1-1/2″ (122 m 38 mm) line from their own apparatus as a backup line. Firefighter Phillips and the Engine 10 officer entered through the door on Floor 1, Side A (see Figure 2) while the other member of their crew remained at the door to assist in advancing the line.

Truck 15, the first due truck arrived at 00:23 and positioned on Side A in the parking lot behind Engine 26. The crew of Truck 15 began laddering Floor 2, Side A, and removed kitchen window on Floor 1, Side A (see Figure 2). Due to security bars on the window, one member of Truck 15 entered the building and removed glass from the window from the interior. After establishing horizontal ventilation, Truck 15 accessed the roof via a portable ladder and began vertical ventilation operations.

Engine 17, the second due engine, arrived at 00:24, laid a 3″ (76 mm) supply line from the intersection of Banneker Drive and Cherry Road NE, to a position on Cherry Road NE just past the parking lot, and in accordance with department procedure, stretched a 350′ 1-1/2″ (107 m 38 mm) line to Side C (see Figure 2).

Approaching Cherry Road from Banneker Drive, Battalion 1 observed a small amount of fire showing in the basement and assigned Truck 4 to Side C. Battalion 1 parked on Cherry Road at the entrance to the parking lot, but was unable to see the building, and proceeded to Side A and assumed a mobile command position.

Second due, Truck 4 proceeded to Side C and observed what appeared to be a number of small fires in the basement at floor level (this was actually flaming pieces of ceiling tile which had dropped to the floor). The officer of Truck 4 did not provide a size-up report to Command regarding conditions on Side C. Truck 4, removed the security bars from the basement sliding glass door using a gasoline powered rotary saw and sledgehammer. After clearing the security grate Truck 4, broke the right side of the sliding glass door to ventilate and access the basement (at approximately 00:27) and then removed the left side of the sliding glass door. The basement door on Side C was opened prior to Engine 17 getting a hoseline in place and charged. After opening the sliding glass door in the basement, Truck 4 attempted to ventilate windows on Floor 2 Side C using the tip of a ladder. They did not hear the glass break and believing that they had been unsuccessful; they left the ladder in place at one of the second floor windows and continued with other tasks.

Figure 2. Location of First Alarm Companies and Hoselines

app_position

Note: Adapted from Report from the Reconstruction Committee: Fire at 3146 Cherry Road NE, Washington DC, May 30, 1999, p. 27. District of Columbia Fire & EMS, 2000.

Unknown to Truck 4, these windows had been left open by the exiting occupants. Truck 4B (two person team from Truck 4) returned to their apparatus for a ladder to access the roof from Side C. Rescue 1 arrived at 00:26 and reported to Side C after being advised by the male occupant that everyone was out of the involved unit (this information was not reported to Command). Rescue 1 and Truck 4 observed inward air track (smoke and air) at the exterior basement doorway on Side C and an increase in the size of the flames from burning material on the floor.

Engines 26 and 10 encountered thick smoke and moderate temperature as they advanced their charged 1-1/2″ (38 mm) hoselines from the door on Side A towards Side C in an attempt to locate the fire. As they extended their hoselines into the living room, the temperature was high, but tolerable and the floor felt solid. It is important to note that engineered, lightweight floor support systems such as parallel chord wood trusses do not provide reliable warning of impending failure (e.g., sponginess, sagging), failure is often sudden and catastrophic (NIOSH, 2005; UL, 2009).

Prior to reaching Side C of the involved unit, Engine 17 found that their 350′ 1-1/2″ (107 m 38 mm) hoseline was of insufficient length and needed to extend the line with additional hose.

Engine 12, the fourth arriving engine, picked up Engine 17’s line, completed the hoselay to a hydrant on Banneker Drive (see Figure 2). The crew of Engine 12 then advanced a 200′ 1-1/2″ (61 m 38 mm) hoseline from Engine 26 through the front door of the involved unit on Side A and held in position approximately 3′ (1 m) inside the doorway. This tactical action was contrary to department procedure, as the fourth due engine has a standing assignment to stretch a backup line to Side C.

Rescue 1’s B Team (Rescue 1B) and a firefighter from Truck 4 entered the basement without a hoseline in an effort to conduct primary search and access the upper floors via the interior stairway. Engine 17 reported that the fire was small and requested that Engine 17 apparatus charge their line.

Questions

Consider the following questions related to the interrelationship between strategies, tactics, and fire behavior:

  1. Based on the information provided to this point, what was the stage of fire development and burning regime in the basement when Engine 26 entered through the door on Floor 1, Side A? What leads you to this conclusion?
  2. What impact do you believe Truck 4’s actions to open the Basement door on Side C will have on the fire burning in the basement? Why?
  3. What is indicated by the strong inward flow of air after the Basement door on Side C is opened? How will this change in ventilation profile impact on air track within the structure?
  4. Did the companies at this incident operate consistently with DC Fire & EMS SOP? If not, how might this have influenced the effectiveness of operations?
  5. Committing companies with hoselines to the first floor when a fire is located in the basement may be able to protect crews conducting search (as outlined in the DC Fire & EMS SOP). However, what building factors increased the level of risk of this practice in this incident?

More to Follow

My next post will examine the extreme fire behavior phenomena that trapped Firefighters Phillips, Mathews, and Morgan and efforts to rescue them.

Master Your Craft

Remember the Past

This week marked the anniversary of the largest loss of life in a line-of-duty death incident in the history of the American fire service. Each September, we stop and remember the sacrifice made by those 343 firefighters. However, it is also important to remember and learn from events that take the lives of individual firefighters. In an effort to encourage us to remember the lessons of the past and continue our study of fire behavior, each month I include brief narratives and links to NIOSH Death in the Line of Duty reports and other documentation in my posts.

September 9, 2006
Acting CAPT Vincent R. Neglia
North Hudson Regional Fire & Rescue Department, NJ

Captain Neglia and other firefighters were dispatched to a report of fire in a three-story apartment building in Union City. Upon their arrival at the scene, firefighters found light smoke and no visible fire. Based on reports that the structure had not been evacuated, Captain Neglia and other firefighters entered the building to perform a search. Due to the light smoke conditions, Captain Neglia was not wearing his facepiece.

Captain Neglia was the first firefighter to enter an apartment. Conditions deteriorated rapidly as fire in the cockloft broke through a ceiling . Captain Neglia was trapped by rapid fire progress and subsequent collapse. Other firefighters came to his aid and removed him from the building. Captain Neglia was transported to the hospital but later died of a combination of smoke inhalation and burns.

NIOSH did not investigate and prepare a report on the incident that took the life of Captain Neglia.

Ed Hartin, MS, EFO, MIFireE, CFO

References

District of Columbia (DC) Fire & EMS. (2000). Report from the reconstruction committee: Fire at 3146 Cherry Road NE, Washington DC, May 30, 1999. Washington, DC: Author.

Madrzykowski, D. & Vettori, R. (2000). Simulation of the Dynamics of the Fire at 3146 Cherry Road NE Washington D.C., May 30, 1999, NISTR 6510. August 31, 2009 from http://fire.nist.gov/CDPUBS/NISTIR_6510/6510c.pdf

National Institute for Occupational Safety and Health (NIOSH). (1999). Death in the line of duty, Report 99-21. Retrieved August 31, 2009 from http://www.cdc.gov/niosh/fire/reports/face9921.html

National Institute for Occupational Safety and Health (NIOSH). (2005). NIOSH Alert: Preventing Injuries and Deaths of Fire Fighters Due to Truss System Failures. Retrieved August 31, 2009 from http://www.cdc.gov/niosh/fire/reports/face9921.html

Lessons Learned: The Way Forward

Monday, October 27th, 2008

Quantitative Analysis

Quantitative analysis of firefighter injuries and fatalities uses statistics to describe what has occurred and identify patterns and trends. Annual reports and longitudinal (multi-year) quantitative studies provide one way to examine firefighter safety performance.

Examination of firefighter fatalities and injuries over time requires consistency of method when comparing data from year to year. However, dividing fatalities and injuries into a small number of causes or injury or death provides a coarse grained picture of the problem. This is useful, but not sufficient.

Reporting system limitations in dealing with multiple causal and contributing factors also limits firefighter injury and fatality statistical analysis and reporting. Quantitative analysis is extremely useful in identifying trends and pointing to issues needing further examination. Identification of the increasing rate of firefighter fatalities inside buildings during structural firefighting is one example. However data and system limitations may preclude a fine grained quantitative analysis of this issue.

Qualitative Analysis

Qualitative analysis of firefighter injuries and fatalities often involves examination of individual incidents, describing in detail what happened in that specific case and identifying causal and contributing factors. The limited information provided by annual reports and longitudinal analysis of firefighter injuries and fatalities can be enhanced by examining individual cases.

The NIOSH Firefighter Fatality Investigation and Prevention Program investigates many firefighter fatalities as a result of trauma (see the NIOSH Decision Matrix). However, they do not generally investigate non-fatal incidents and do not investigate near miss events. In addition to not examining all traumatic fatalities there is often a considerable delay in beginning the investigative process. This delay may result in the building involved being demolished and loss of important detail in witness interviews.

My last two posts looked at the US Forest Service approach to Investigating Wildland Fire Entrapments and Peer Review Process to identify lessons learned. Application of these methods in structural firefighting would provide an excellent method for improving our understanding of applied fire dynamics, tactical operations, and decision-making as well as other hazards such as structural collapse, and firefighter disorientation.

The Way Forward

Fire service organizations should examine all events that involve structural fire entrapment, collapse entrapment, and disorientation. There are no commonly accepted definitions for these types of events. However, the US Forest Service definition for wildland fire entrapment could serve as a starting point for defining entrapment and disorientation in the structural environment.

  • Structural Fire Entrapment: a fire behavior related event involving compromise of normal (planned) means of egress; or thermal exposure resulted in, or had significant potential for death, injury, or damage to personal protective equipment.
  • Collapse Entrapment: A structural failure related event involving compromise of normal (planned) means of egress, or impact resulting from structural failure (load bearing or non-load bearing) that resulted in, or had significant potential for death, injury, or damage to personal protective equipment.
  • Disorientation Entrapment: Loss of spatial orientation while operating in a hazardous atmosphere that resulted in, or had significant potential for death or injury.

Note that like the US Forest Service definition of wildland fire entrapment; these events are inclusive of fatalities, injuries, and near miss events.

Investigating a near miss or accident involving a serious injury or fatality may present significant challenges to an individual agency in terms of resources and expertise. Individuals and organizations also filter information through cultural norms which define ā€œthe way we do thingsā€. Use of a multi-agency team reduces these potential challenges. However, as in emergency response, it is important to define the process and develop effective working relationships prior to facing a serious injury or fatality investigation.

Who should be involved? Adapting from the US Forest Service Investigating Wildland Fire Entrapments individuals with the following skill sets should be involved in structural fire, collapse, or disorientation entrapment events.

  • Command Officer
  • Safety Officer
  • Fire Behavior Specialist
  • Structural Specialist (collapse entrapment)
  • Fire Investigator
  • Personal Protective Equipment Specialist (may be an external resource)
  • Photographer/Videographer

There are a number of considerations in determining the makeup of the investigative team. Depending on the nature of the investigation, some of these skill sets may not be as critical or a single individual may fill more than one role (e.g., fire investigator and photographer). Unlike the wildland community, there is considerably less clarity to specialization in structural fire behavior. In some cases this may be a fire investigator with specific training in fire dynamics and fire modeling, in others it may be a compartment fire behavior instructor. This will depend on the nature of the incident and available resources. In addition, the technical complexity of assessing personal protective equipment performance (particularly self-contained breathing apparatus) may require specialized external expertise.

As in wildland incidents, there is also great value in peer review of structural incidents. Like the more formal investigation, peer review is a team based process, but the team is comprised of a small group of experienced firefighters and fire officers who are known to be insightful, fair, just, and honest.

A Call to Action

There is not a simple cookbook approach to developing processes for entrapment investigation and peer review. The first step is to identify how your organization can effectively identify and communicate lessons learned. While serious accidents and injuries present a significant challenge, near miss events occur much more frequently and provide an opportunity for individual and organizational learning as well as an opportunity to develop the entrapment investigation and peer review processes. The following two actions provide the opportunity to improve firefighter safety while operating offensively at structure fires:

  • Members submit near miss reports to the National Firefighter Near Miss Program
  • Agencies use a team based, multi-agency approach to investigate structure fire, collapse, and disorientation entrapments (inclusive of near miss events).
  • Agencies widely share their lessons learned with other fire service agencies and organizations

Please post your thoughts on this process and how we can best develop and communicate lessons learned from entrapment events occurring during structure fires.

Ed Hartin, MS, EFO, MIFireE, CFO

Entrapment Investigation & Lessons Learned

Monday, October 20th, 2008

Structural firefighting agencies can draw some valuable lessons from the wildland firefighting community. Fire behavior training in many structural agencies often begins and ends in recruit academy. For wildland firefighters, fire behavior training involves an extensive, multi-level curriculum (S-190, S290, S-390, S-490 and so on). The wildland community is also more substantively engaged in analysis of fatalities, accidents, and near miss events with the intention of impacting policy, procedure, and performance. This is not to say that they have a perfect safety record, far from it. However, this ongoing effort to identify and implement best practice based on lessons learned is worthy of emulation.

The US Forest Service Technology & Development Program produced a document titled Investigating Wildland Fire Entrapments which outlines the process that should be used and documentation required for entrapment related incidents. Entrapments are:

A situation where personnel are unexpectedly caught in a fire behavior related, life-threatening position where planned escape routes and safety zones are absent, inadequate, or have been compromisedā€¦These situations may or may not result in injury. They include”near misses”.

The concept of entrapment applies equally in the structural firefighting environment. I read news accounts of extreme fire behavior related events (e.g., flashover, backdraft) from around the United States on a weekly basis. Flashover, backdraft, or other extreme fire behavior often results in a near miss or minor injury and less frequently in serious injury or fatality. Some (actually very few) of these incidents are documented in the National Firefighter Near Miss Program. As discussed in my last post, the near miss program uses self-reported data. This is extremely useful in determining the individual’s perception of the event and what lessons they took away from the experience. However, the individual reporting the event may or may not have the training or education to recognize what actually happened, determine multiple causal factors, and provide a reasonably objective analysis.

Formal Investigation

If a significant injury occurs, some level of investigation is likely to take place (even if it is limited to a cursory examination of circumstances and conditions by the individual’s supervisor). Traumatic fatalities result in more significant and in many cases multiple investigations by the agency involved, law enforcement agencies, Occupational Safety and Health Administration (state or federal), and potentially the National Institute for Occupational Safety and Health (NIOSH). The purpose of these various investigations is different and not all focus on identifying lessons learned and opportunities for improving organizational performance. However, some reports by the agencies involved, state fire service agencies, and NIOSH take positive steps in this direction. For example:

Limitations

Near miss events and events involving extreme fire behavior resulting in minor injuries or damage to equipment frequently are not or are inadequately investigated to identify causal factors and lessons learned. Investigation of serious injuries and fatalities in many cases do not adequately address fire behavior and interrelated human factors that may be directly or indirectly related to the cause of the incident. This results in lost opportunities for individual and organizational learning.

Two interrelated challenges make investigating extreme fire behavior events or structural fire entrapments difficult. First is the lack of a formal process or framework for this specific type of investigation and second is potential for investigators lack of specific technical expertise in the area of fire behavior.

A Solution

The US Forest Service uses a team approach to investigating entrapment incidents. The team may include (but is not limited to):

  • Fire Operations Specialist (Operations Section Chief level)
  • Fire Safety Officer
  • Fire Behavior Analyst, with experience in the incident fuel type
  • Fire Weather Meteorologist
  • Fire Equipment Specialists who develop the personal protective equipment (including fire shelters) used on wildland fires
  • Technical Photographer
  • Fire Information Officer

This team is established and begins the investigation as soon as possible after the occurrence of the event to ensure that critical information and evidence is not lost. The investigative process and documentation focuses on accurately describing what happened, when it happened, causal and contributing factors, and recommendations to reduce the risk of future occurrence.

What might this look like in the structural firefighting environment?

Communicating Lessons Learned

Lessons learned must be integrated into appropriate training curriculum to ensure that the lessons are built into organizational culture.

Some agencies have taken steps in this direction. Following the line-of-duty death of Technician Kyle Wilson, Prince William County Department of Fire & Rescue conducted an in-depth investigation which integrated use of computational fluid dynamics (CFD) modeling to describe likely fire conditions and the influence of wind on fire behavior. Following the conclusion of this investigation, the report and related presentations have been distributed widely.

Investigating Wildland Fire Entrapments identifies timeliness as being essential in dissemination of the lessons learned. This presents a significant challenge when faced with a complex event involving a major injury or fatality. However, it is likely that timeliness in communicating lessons learned can be improved without compromising the thoroughness and quality of the investigation.

My next post will examine the US Forest Service’s less formal Peer Review Process which may be used following near miss events or significant events regardless of outcome (possibly concurrently with a formal investigation). Like the entrapment investigation procedure, there are likely some lessons here for the structural firefighting community!

Ed Hartin, MS, EFO, MIFireE, CFO