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The Bowstring Truss

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The Bow String Truss

The Bowstring Truss:
There’s a tremendous lack of understanding in the American Fire Service as to what accurately defines and comprises a Heavy Timber Bowstring Truss and the Operational and Safety Precautions that must be recognized, implemented and trained on, in order to achieve and maintain operational excellence, company integrity and firefighter safety on the fireground.

All bowstring trusses are not created equal and do not share the same characteristics when found in a building and occupancy.

They may have the same shape, but shape alone does not define the bowstring truss.
Based on the type, design, construction, materials, age, span, spacing, configuration, occupancy and application there are vast differences AND similarities.

There are significant differences in terminology when referring to them and tactics that should be employed on the fireground- and yes there are prominent differences between east coast and west coast types and tactics.

The Bowstring Truss- They are not All the Same

Do you know what they are?

I’m working on an article series for a major fire service publication with on-line accompaniments that will provide uniformity and clarity on the subject and the much needed continuity so were’ talking the same language.For the mean time let me offer the following terms that some of you may be familiar with – in your world. Here are some Bowstring Type Truss terms:

  • The Heavy Timber Bowstring Truss,
  • Arch-Rib Bowstring Truss,
  • Laminate Cord Bowstring Truss,
  • Lattice Bowstring Truss,
  • Easybow Truss,
  • Mack Truss,
  • Summerbell Bowstring Truss,
  • Mono-chord Bowstring Truss
  • Duo-Chord Bowstring Truss,
  • Segmental Multi-Cord Bowstring Truss,
  • Tension Rod Bowstring Truss,
  • Bowstring Arch Truss,
  • Bowstring K-Truss,
  • Split-Ring Bowstring Truss…..to name a few.

We’ll be posting lots more on this on CommandSafety.com as well as expanded coverage on Buildingsonfire.com …. Stay Tuned

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A Delicate Balance

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A Delicate Balance

 

Light Weight construction has given way to Engineered Structural Systems (ESS) which in today’s evolving fireground, have an even more extensive array of performance, operational and integrity issues that affect a building’s performance under fire conditions.To unequivocally state that nothing has changed in buildings, occupancies, fire flow delivery rates and demands for increased proficiencies of our firefighters, company and command officers is absurd, ignorant and dangerous.

“It’s a lot more than just Stretching the Line…and going in….”

 
Building Knowledge=Firefighter Safety…so we can do our job—and that’s firefighting .Another classic illustration by Paul Combs.

Another classic illustration by Paul Combs

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Engineered Structural Support (ESS) system: Been in the Field lately?

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Been in the field lately looking at your buildings under construction? Here’s a new look at a common Engineered Structural Support (ESS) system.

Here’s  today’s Taking it to the Streets session; Take a look at this Engineered Structural Support (ESS) system. There are two critical component systems depicted here in this photo- can you tell what they are? Take a close look at the ESS T…russ components. They are nothing new, but they do cause a stir when they make their way back into main stream fire service discussions as firefighters and officers “rediscover” these type of systems, their use, presence and operational risk and profiling.

So let’s start the dialog:

  • Can you name the type of ESS Truss, the inherent characteristics, design and function | typical applications | risks and operational concerns.
  • What impact will fire impingement have on the ESS assembly in either foor or roof systems?
  • How can you identify these assemblies and building characteristics unpon arrival?
  • What fireground strategies and tactics would you employ upon arrival at an occupancy with this type of ESS?
  • Don’t forget to look at the second system component that I mentioned earlier;
  • Can you identify it? Its relationship to the other system and other inherent performance issues?

 

 

Lots to talk about, look at and share. Any street stories to share-please post. I’ve got a few more in this series to post after we get some dialog and insights….
We’ve cross posted this on our Buildingsonfire Facebook page (HERE), if you haven’t checked it out, please follow the link, there’s been some great discussions and insights being shared from around the country…
Don’t forget to spread the word about Buildingsonfire.com \ CommandSafety.com and Buildingsonfire on FB…send the links along and like….Dont forget about CommandSafety on Twitter and Buildingsonfire on twitter also.

Eleven Minutes to Mayday; What You Need to Know

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The Colerain Township (OH) Fire and EMS Department under the leadership of Director and Chief G. Bruce Smith recently released its final report Investigation Analysis of the Squirrels nest Lane Firefighter Line of Duty Deaths related to the April 4, 2008 Double Line of Duty Death of a Captain and Firefighter.  This investigative analysis and report, although specific to the events and conditions encountered during the conduct of operation at the residential occupancy at 5708 Squirrels nest Lane has pertinent and relevant insights, recommendations and factors that all Fire Service personnel, regardless of rank should read.

This is one of those distinctive reports that has influential and critical operational, training and preparedness elements embedded throughout the report. Following my review of the report, having previously read the preliminary report findings, it is apparent there continues to be common threads shared by this and other events and incidents where a single of multiple firefighters have lost their lives due to similarities in the apparent and common cause deficiencies and short comings identified.

All company and command officers should read and comprehend the lessons learned. Then, take these new found insights and see what the gaps are at the personal level (yours or those you supervise) as well as the shift, group, station, battalion, division or department as a whole. If there are gaps, then identify a way to implement timely changes as necessary so there are No History Repeating (HRE) events.

I have provided a comprehensive synopsis of the report for your review. Take the time to read the entire report, make the time to improve where you need to.  

On Friday, April 4, 2008 at 06:13:02 hours, what began as a routine response for Colerain Township Fire and EMS Engine 102 to investigate a fire alarm activation at 5708 Squirrels nest Lane, Colerain Township, Ohio resulted in the deaths of Colerain Township Captain Robin Broxterman and Firefighter Brian Schira.

Upon their arrival at the scene of the two-story wood framed, residential building working fire conditions existed in the basement. The initial attack team consisted of Broxterman, Schira, and one other firefighter. The team advanced a 1¾-inch attack hose line through the interior of the building for fire control.

Even though, they were provided with some of the most technologically advanced protective clothing for structural firefighting and self-contained breathing apparatus, it appeared that Broxterman and Schira were overwhelmed by severe fire conditions in the basement. 

During their attempt to evacuate the building, the main-level family room flooring system in which the two were traveling on collapsed into the basement trapping the firefighters. Eleven minutes elapsed from time of arrival to the catastrophic chain of events.

The investigation of this incident provided a number of findings and recommendations that should be considered by Colerain’s fire department, as well as other fire department organizations. The examination encompassed issues that related to building construction, firefighting tactics, command and control, situational awareness, communications, training, firefighting equipment and the individual responsibility of firefighters of the Colerain Township Department of Fire and Emergency Medical Services (Colerain Fire & EMS). In addition, a segment of the examination included a review of the individual and group affects following such an event, and the measures initiated that attempted to ensure individual, family and organizational wellness.

The following factors were believed to have directly contributed to the deaths of Captain Broxterman and Firefighter Schira:

  • A delayed arrival at the incident scene that allowed the fire to progress significantly;
  • A failure to adhere to fundamental firefighting practices; and
  • A failure to abide by fundamental firefighter self-rescue and survival concepts

 Although the aforementioned factors were believed to have directly contributed to their deaths, they might have been prevented if:

  • Some personnel had not been complacent or apathetic in their initial approach to this incident;
  • Some personnel were in a proper state of mind that made them more observant of their surroundings and indicators;
  • The initial responding units were provided with all pertinent information in a
  • timely manner relative to the incident;
  • Personnel assigned to Engine 102 possessed a comprehensive knowledge of their first-due response area;
  • A 360-degree size-up of the building accompanied by a risk – benefit analysis
  • was conducted by the company officer prior to initiating interior fire suppression operations;
  • Comprehensive standard operating guidelines specifically related to structural
  • firefighting existed within the department;
  • The communications system users (on-scene firefighters and those monitoring the incident) weren’t all vying for limited radio air time;
  • The communications equipment and accessories utilized were more appropriate for the firefighting environment;
  • Certain tactical-level decisions and actions were based on the specific conditions;
  • Personnel had initiated fundamental measures to engage in if they were to become disoriented or trapped inside a burning building; and
  • Issued personal protective equipment was utilized in the correct manner.

 Incident Reported

On Friday, April 4, 2008, at 06:11:23, the Hamilton County Communications Center (HCCC) received notification of an automatic alarm activation (smoke detector and carbon monoxide) at 5708 Squirrels nest Lane (LN).

  • An automatic fire alarm response complement of two engine companies (Engines 102 & 109), one ladder company (Ladder 25), and the Battalion Chief (District 25) were dispatched to investigate at 06:13:02.
  • At 06:13:43, a second notification was received from the female homeowner reporting a fire in the basement of the building.
  • At 06:20:43, a third notification by means of a cellular phone from the female homeowner to HCCC routed through the City of Cincinnati’s Fire and Police Communications Center was received.
  • At 06:22:41, the initial response complement was then upgraded to a building fire, also known as a structure fire response complement to include one additional engine company (Engine 25), one rescue company (Rescue 26), and one basic life support transport unit (Squad 25).

Property and Building Description: The building at 5708 Squirrels nest LN was a single-family residence that set back approximately 450-feet from the street at the end of a private driveway on a heavily wooded lot.

  • The building was two-stories in height, approximately 45-feet wide by 30-feet deep with a finished below-grade (basement) living space and attached two-car garage.
  • For simplicity, the report refers to the living space under the main-level of the building as a basement.
  • From the front (side Alpha), the building was two-stories above grade. The vertical distance between floors was approximately eight-feet. The exterior main entrance was located in the front middle of the building approximately one-foot above grade level.
  • Additional entrances to the first-floor living space were by means of a rear entry door from an upper-level deck area and through the garage area.
  • The interior stairway to the basement was located approximately 15-feet from the front main entry door towards the rear of the building. There were no exposed buildings on the adjacent sides of the fire building.

The building was located approximately 450-feet from the curb and a driveway leading to the front entrance. The nearest fire hydrant was located approximately 500- feet from the front entrance. To provide for uniform identification of locations and operationalforces at the incident scene, the scene was divided geographically into smaller parts, which were designated as sectors. Specific areas of the incident scene were designated as follows:

  • The side of the building that bears the postal address of the location was designated as Side Alpha or front by the Incident Commander;
  • The property sloped downward towards the rear (side Charlie) of the building with an approximate 13-foot elevation difference from side Alpha to Charlie. The
  • Charlie side of the building was three-stories above the rear grade level with the building’s basement floor approximately five-feet above grade level. The exterior entrance to the building’s’ basement area, also known as a walk-out was by means of a stairway that led to a wooden deck on the Charlie side adjacent to the Delta side. A second stairway led to an upper level deck that served the main level of the building.

 

Initial Fire Attack Operation: Upon arrival at the incident address, Engine 102 (E102), assigned four personnel (one captain, one fire apparatus operator [FAO], and two firefighters) entered and proceeded down the driveway deploying a five-inch supply hose line.

  • With their apparatus positioned in front of the building Captain (Capt.) Broxterman radioed, “Moderate smoke showing. E102 will be Squirrelsnest Command.” at 06:24:01.
  • Verification was made by the E102’s FAO through face-to-face communication with the male homeowner that all occupants were out of the building, which was then relayed to Capt. Broxterman.

District 25 (D25) arrived at the scene at 06:26:35 and assumed Command from Capt. Broxterman. Capt. Broxterman, Firefighter (Ffr.) Schira and E102’s Ffr. #2 advanced a 1¾-inch pre-connected hose line through the front main entrance. The fire was determined to be located in the basement of the building.

  • At 06:27:52, Capt. Broxterman radioed, “E102 making entry into the basement, heavy smoke”.
  • At 06:30:35, E109′s captain radioed, “Command from E109, contact 102,have them pull out of the first floor, redeploy to the back. It’s easy access. Conditions are changing at the front door.”
  • At 06:34:48, Engine 25 (E25), the designated Rapid Assistance Team, had just completed their 360-degree size-up around the building, and encountered E102’s Ffr. #2 in front of the building, whom reported that he had lost contact with his crew.
  • During the time period between 06:29:24 and 06:34:48, the investigation committee believed that one or more catastrophic events occurred including a failure of the main-level flooring system near the Beta – Charlie corner of the building.

 Rescue and Recovery Operations

  • At 06:35:34, the Incident Commander (IC) identified a potential Mayday operation, which indicates a life threatening situation to a firefighter.  
  • RAT25 was deployed at 06:36:48. The actual Mayday operation was initiated by the IC at 06:37:41 followed by a request at 06:37:53 to the HCCC for a second alarm complement of firefighting resources.  
  • At 06:42:01, RAT25 entered the basement from the rear of the building. At 07:00:27, E26’s personnel entered through the front main entrance of the building and into the basement by means of the interior stairway.  
  • Both missing firefighters were located in the basement near the Charlie side wall adjacent to the Beta side following a floor collapse. Capt. Broxterman and Ffr. Schira were obviously deceased as a result of their injuries. 

Fire Origin and Cause: Information from the property owners was that the female had smelled an odor in the house. She told her husband, who went to investigate. Neither of them observed any smoke or flames at that time. The husband went to the basement, and located a fire near a cedar wood lined closet used to cultivate orchids in the unfinished utility room. He attempted to extinguish the fire with portable fire extinguishers and pans of water. As the fire alarm activated, the husband had his wife call 9-1-1 to report the fire. The state of Ohio Fire Marshal’s Office Fire and Explosion Investigation Bureau ruled the fire to be accidental in nature. The fire was determined to have originated in the unfinished utility room of the basement level in or near the cedar closet. This area was directly below the family room on the first floor. The probable ignition source for this fire was determined to be at and about a plastic air circulation fan and the associated electrical wiring.

Cause of Deaths

Capt. Broxterman was a 37-year old employee of the Colerain Fire & EMS with approximately 17-years of certified firefighting experience. Capt. Broxterman became trapped in the basement area for a prolonged amount of time following the sudden floor collapse. Capt. Broxterman was found positioned face down over top of Ffr. Schira. The majority of her protective clothing ensemble and equipment were heavily damaged as a result of exposure to heat and direct flame impingement. She was pronounced deceased following her removal from the building. Her body was transported to the Hamilton County Coroner’s Office for autopsy. The Coroner’s report cited the manner of death as “accidental” and the cause of death as “burns and inhalation of smoke and superheated and noxious gases.” Capt. Broxterman sustained burns to 100% of her body surface, which ranged from first to fourth degree in severity as described in the coroner’s autopsy report. Postmortem carboxyhemoglobin (COHb), which is a measure of carbon monoxide exposure, was measured at 22% saturation and soot was observed in portions of her upper and lower respiratory system.

  • Based on the injuries sustained and the damage to Capt. Broxterman’s protective clothing ensemble and equipment, it is likely that she was exposed to a rapid intensification of heat and flames in the building’s basement that overwhelmed her protective ensemble and equipment, exposing her body and respiratory system to intense heat and toxic products of combustion.

 Ffr. Schira was a 29-year old employee of Colerain Fire & EMS with approximately 3½-years of certified firefighting experience. He also became trapped in the basement area for a prolonged amount of time following the sudden floor collapse. Ffr. Schira was found positioned on his right side and back, face-up beneath Capt. Broxterman. The majority of his protective clothing ensemble and equipment was heavily damaged as a result of exposure to heat and direct flame impingement. Ffr. Schira was pronounced deceased following his removal from the building. His body was transported to the Hamilton County Coroner’s Office for autopsy. The Coroner’s report cited the manner of death as “accidental” and the cause of death as “burns and inhalation of smoke and superheated and noxious gases”. Ffr. Schira sustained burns to 100% of his body surface, which ranged from first to fourth degree in severity as described in the coroner’s autopsy report. Postmortem COhb was measured at 8% saturation and soot was observed in portions of his upper and lower respiratory system.

  • Based on the injuries sustained and the damage to Ffr. Schira’s protective equipment, it is likely that that he was exposed to a rapid intensification of heat and flames in the building’s basement that overwhelmed his protective ensemble and equipment, exposing his body and respiratory system to intense heat and toxic products of combustion.

Select Findings and Recommendations

Findings, Discussions and Recommendations

FINDING #3.1: The area of fire origin had no finished ceiling, which exposed the floor joists and the underside of the floor decking to direct fire impingement causing rapid deterioration and failure of the flooring system directly underneath the main-level family room.

During this incident, based on communications transcripts (telephone and radio) it’s probable that the fire had advanced from its incipient stage to a free burning stage in approximately 18 to 20-minutes by the time Capt. Broxterman radioed that they were making entry into the basement.

  • As stated in the Incident Overview section, during the time period between 06:29:24 and 06:34:48, it is believed that one or more catastrophic events occurred within the building, which included a failure of the flooring system near the Beta-Charlie corner of the building’s first floor.

It has been widely believed in the firefighting profession that traditional sawn lumber is far superior to some of the more innovative lightweight construction components (e.g., wood I-joist) in use today. With dimensional lumber, two-inch by eight-inch and larger, there is a greater surface to mass ratio to resist the damaging effects of fire and the structural components will maintain their integrity for a longer period of time. While this has traditionally been accurate, this incident clearly shows that this may not always be the case. Heavy charring was evident to structural members in the fire area of origin. Notice the burn damage shows how the wooden floor joists had been burned to and away from the band joist. A band joist is a vertical member that forms the perimeter of a floor system in which the floor joists tie in to. Also known as the rim joist. Early platform framed homes very likely used solid, dimensional lumber and plywood, which provided a reasonable surface to mass ratio. But the later the home was built, the less mass even dimensional lumber has due to the reduction in the actual thickness of solid dimensional lumber provided by the lumber industry through the mid-1900’s. As the years go by, building materials will likely keep getting lighter and lighter and introduce more resins and other chemicals.

 Laboratory tests that exposed structural wood components to the American Society for Testing and Materials (ASTM) E119 Assembly Test indicated that a traditional two-inch by ten-inch structural member failed in 12-minutes and six-seconds. ASTM E119 test is the standard test method for evaluating building and construction materials exposed to fire. Unlike the standardized ASTM test fires, it is widely recognized that real building fires are highly variable in their size, rate of growth and intensity. Responding firefighters are unlikely to know when a given fire started, how hot it had been prior to arrival, how long it had been at any given temperature, the design capacity and actual loads on the floors over the fire or the amount of actual damage that the fire may have done to the joists. All of these factors make it impossible to predict the remaining capacity of a floor by even the most knowledgeable, professional fire experts.

RECOMMENDATION #3.1a: Fire departments should ensure that firefighters and incident commanders are aware that unprotected floor and ceiling joist systems, no matter the type, may fail at a faster rate when exposed to direct fire impingement.

Unfinished basement ceilings and other areas that have exposed joists or trusses jeopardize flooring and roof systems unnecessarily during a fire, causing premature failure. Often, a weakened floor and ceiling joist system can be difficult to detect from above as the floor surface above may still appear intact. Firefighters operating on floors above fire-damaged joist systems may fall through a weakened area and become trapped in a fire below. IC’s and firefighters must be aware that these systems can fail rapidly and without warning, and plan interior operations accordingly.

Firefighters must also be aware that while floor sag may be a widely accepted warning of an impending structural failure, floor sag is not always present or visible prior to a catastrophic collapse in a fire, regardless of the joist type, due to floor coverings, the fire’s intensity, the combination of joist spans and loads present, the location of serious structural fire damage or simply because it is too dark and smoky to see a sag in the floor. This is true for all types of structural joists, including materials such as sawn lumber, wood I-joists, and open web wood trusses and noncombustible members such as lightweight steel joists. The floor covering in this area was carpeting that transitioned to ceramic tile. When unprotected, any traditional or lightweight residential floor or ceiling assembly material, either combustible or noncombustible, may fail within several minutes of the fire’s ignition. It makes sense, therefore, that when there is a serious fire beneath a floor, there is no predictable safe amount of time that anyone can remain on that floor. Any floor system protected or not, can fail unpredictably when exposed to a substantial fire beneath.

FINDING # 4.2: E102′s officer failed to properly analyze the scene by not performing a 360-degree scene size-up to determine an overall strategy, and implement safe and effective firefighting tactics.

After the apparatus was positioned in front of the building, E102’s FAO was ordered by Capt. Broxterman to, “Ask the homeowner where the fire [location] was”, which was indicated to be in the basement by the male homeowner. As this was taking place, Capt. Broxterman continued donning her protective clothing ensemble (coat, helmet and self-contained breathing apparatus). Although E102′s officer provided a brief radio report of conditions observed upon arrival, she did not properly evaluate the scene so as to develop a basic strategy for implementation of safe and effective firefighting tactics. Had the officer visually evaluated the Charlie side of the building, the advanced fire conditions may have been noted, and that the lower level fire area was accessible by means of an exterior entry door for a more direct fire attack from the interior unburned side.

This means that firefighters enter a building and position the attack hose line between the fire and the uninvolved portions of the building. This direction of fire attack is preferred because it is likely to contain the fire, protect occupants, and push heat and gases out of the building if ventilation has been performed. On the other hand, danger increases significantly when attacking from the unburned side and is not always practical based on fire location, intensity, and building construction.

It cannot be conclusively known as to why Capt. Broxterman and Ffr. Schira proceeded into the area of the building that eventually collapsed resulting in their deaths. The investigation committee has concluded that the most probable explanation is that E102′s three-person interior team was successful in advancing their uncharged attack hose line into the basement recreation room area; reaching a point approximately 10 to15-feet from the bottom of the basement stairway as shown in the Incident Overview chapter. Once the team reached this area, it was realized they did not have sufficient hose line to continue advancing towards the seat of the fire. The team’s third member (Ffr. #2) reversed his travel and made his way back to the exterior of the building to advance additional hose line. As the team of two waited for additional hose line to be stretched and the hose line to be charged by the pump operator, the interior conditions rapidly deteriorated to a stage that it became untenable for them to hold their position.

The team evacuated back-up the stairway without following the hose line, which by all indications was tight up against the stairway wall and tightly wrapped around the stairway door entry. Once at the top of the stairway, one of the two deceased, if not both were likely in some form of distress; became disoriented and proceeded into the family room in a direction opposite the route of travel from which they entered the building. As the two moved across the family room floor, the flooring system collapsed into the utility room area of the basement. When the third team member re-entered the building, he was unable to locate the other two members.

The inability of Ffr. #2 to locate his team and the loss of radio communications contact with the interior team prompted the IC to declare a Mayday and activation of the RATs. This incident resulted in tragedy primarily due to the concealment of several burned-through floor joists under the carpet covered flooring system, which was nearly impossible to recognize due to heavy smoke conditions inside the burning building.

The following factors are believed to have directly contributed to the deaths that occurred in this incident:

  • The delayed arrival at the incident scene allowed the fire to progress significantly and the hazardous conditions to exponentially increase;
  • The failure to adhere to fundamental firefighting practices (e.g., entry into an enclosed building with obvious working fire conditions without a charged attack hose line)
  • The failure to abide by the fundamental concepts of fire fighter self-rescue and survival (e.g., following of the hose line in the direction of travel back to the building’s entrance or exit).

 Although the aforementioned factors are believed to have directly contributed to the deaths reported here, they might have been prevented if:

  • Some personnel had not been complacent or apathetic in their initial approach to this incident which eventually led to being overwhelmed in their response to their initial findings;
  • Some personnel were in a proper state of mind that made them more observant of their surroundings and indicators, and the potential threats and risks that presented themselves;
  • The initial responding units were provided with all pertinent information in a
  • timely manner relative to the incident, especially critical was the information  given to the emergency communications center from the homeowners reporting an actual fire
  • Personnel assigned to E102 possessed a comprehensive knowledge of their firstdue response area specifically related to road and street locations, and any particular characteristics related to those areas.
  • A 360-degree size-up of the building accompanied by a risk – benefit analysis was conducted by the company officer prior to initiating interior fire suppression operations; the risk of an action must be weighed against the probable benefit that may be reasonably and realistically expected.
  • Comprehensive standard operating guidelines specifically related to structural firefighting existed within the department;
  • The communications system users (on-scene firefighters and those monitoring the incident) weren’t all vying for limited radio air time. This competition led to missed and distorted messages and less than efficient use of resources, which exacerbated the problems of already taxed communications.
  • The communications equipment and accessories utilized were more appropriate for the firefighting environment;
  • Certain tactical-level decisions and actions were based on the specific conditions as encountered with an emphasis placed on fire ground tactical priorities (i.e., life safety, incident stabilization and property conservation);
  • Personnel had initiated fundamental measures to engage in if they were to become disoriented or trapped inside a burning building; and
  •  Issued personal protective equipment was utilized in the correct manner.

In Memory

The Colerain Township (OH) Department of Fire and Emergency Medical Services’s report examined the events of April 4th, 2008 with the benefit of hindsight, while seeking to be independent, impartial, and thorough. From the beginning, Colerain Fire & EMS has been committed to share our findings with others in the hope that it may prevent another such event.

The deaths of Captain Robin M. Broxterman and Firefighter Brian Schira had a profound loss not only to their parents, family and this organization, but also to the larger fire service community. In order to prevent these tragic losses in the future, we must first understand how and why our sister and brother firefighters died. We must learn from their incident and take that knowledge forward. If it was possible, what would these firefighters tell us today that might prevent a similar death of a firefighter in the future? What would they want us as firefighters, company officers and chief officers to know about the circumstances that lead to their deaths and the things we (and they) might have done to alter the most tragic of outcomes?  

From the information that was made available for review, it was evident that these two individuals were well-loved in life, and greatly missed in death. Every line of duty death of a firefighter in the United States is significant. This investigative analysis document is dedicated to Captain Broxterman and Firefighter Schira, their families, friends and the community whose lives were forever changed. In working to improve the health and safety of all United States firefighters, we have much to learn from the supreme sacrifice of these two individuals, who they were in life and in death. We honor their memories.

  

References

  • Colerain Township Department of Fire and Emergency Medical Services, Web Site HERE
  • Investigation Analysis of the Squirrels nest Lane Firefighter Line of Duty Deaths April, 2010 Full Report HERE
  • NIOSH Fire Fighter Fatality Investigation Report F2008-09| CDC/NIOSH July, 2009, Report HERE
  • WLTW.com news report Summary HERE

  

 

Predictability of Occupancy Performance during Suppression Operations

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2-2-2009 3-20-14 PMOur buildings have changed; the structural systems of support, the degree of compartmentation, the characteristics of materials and the magnitude of fire loading. The structural anatomy, predictability of building performance under fire conditions, structural integrity and the extreme fire behavior; accelerated growth rate and intensively levels typically encountered in buildings of modern construction during initial and sustained fire suppression have given new meaning to the term combat fire engagement.

The rules for combat structural fire suppression have changed, but we have yet to write the rule book from which the new games plans must be derived. We seek the elusive “Rosetta stone” that aligns and interprets the emerging and traditionalist acumen related to fire stream effectiveness, flow rates, cooling capacity, extreme fire behavior and fire dynamics, compartment fire theory, propagation and cooling capacity and tactical deployment all relate towards defining an engineering approach to firefighting tactics versus the manual, labor-driven tactics of line deployment and rudiment placement of water on a fuel source within the fire compartment (room).

It’s no longer just brute force and sheer physical determination that defines structural fire suppression operations. It begs to suggest that many of today’s incident commanders, company officers and firefighters lack the clarity of understanding and comprehension that correlate to the inherent characteristics of today’s buildings, construction and occupancies and the need for refined engine company operations within the modern building construction setting. We assume that the routiness or successes of our operations and incident responses equates with predictability and diminished risk to our firefighting personnel.

The work of such notable suppression theory pioneers as P. Grimwood, E. Hartin, S. Särdqvist and S. Svennson and the concepts surrounding 3D firefighting, B-SAHF and other emerging research from the NIST and UL are areas that today’s discerning and progressive fire officer and commanders must become well-informed and conversant. The quantitative scientific data and emerging concepts from continuing research and testing such as the NIST’s Wind Drive Fire Studies and UL’s The Structural Stability of Engineered Lumber in Fire Conditions are providing enlightenment on fire development, fuel controlled and ventilation controlled fire development, operational time-duration parameters and degradation and failure mechanisms related to compromise and structural collapse in occupancies.

Our current generation of buildings, construction and occupancies are not as predictable as past conventional construction, therefore risk assessment, strategies and tactics must change to address these new rules of combat structural fire engagement.

  • Building Construction Systems
    • Heritage
      • Pre-1919
    • Legacy
      • 1920-1949
    • Conventional
      • 1950-1979
    • Engineered
      • 1980-2010
    • Hybrid
    • Chameleon

The fundamental compartment that comprised a typical room configuration in terms of area (square footage), volume (height/Width), furnishings (fire load package) and materials of construction (structural anatomy) found within conventional, legacy or heritage construction provided predictability in terms of fire suppression, fire behavior, operational time and survivability (civilian/firefighter). The dramatic changes since the early 1980’s in the evolution of modern building construction and the institutionalization of engineered structural systems (ESS) have created compartment (room) areas in excess 500 SF, volumes that are open and spaciously interconnected to other habitable space, fire load packages that create extreme fire behavior, compromising structural stability in shorter time spans creating decreasing interior operational time and requiring increasing fire flow rates and volume to sustain requisite extinguishment demands.

Commanders and Company Offices need to gain new insights and knowledge related to the modern building occupancy and to modify and adjust operating profiles in order to safe guard companies, personnel and team compositions. Strategies and tactics must be based on occupancy risk not occupancy type and must have the combined adequacy of sufficient staffing, fire flow and nozzle appliances orchestrated in a manner that identifies with the fire profiling, predictability of the occupancy profile and accounts for presumed fire behavior. Today’s engine company operations and fire suppression theory has to progress beyond the pragmatic approaches to fire suppression such as “Big Fire-Big Water principle.

When we look at various buildings and occupancies, past operational experiences; those that were successful, and those that were not, give us experiences that define and determine how we access, react and expect similar structures and occupancies to perform at a given alarm in the future. Naturalistic (or recognition-primed) decision-making forms much of this basis. We predicate certain expectations that fire will travel in a defined (predictable) manner that fire will hold within a room and compartment for a predictable given duration of time; that the fire load and related fire flows required will be appropriate for an expected size and severity of fire encountered within a given building, occupancy, structural system; in addition to having an appropriately trained and skilled staff to perform the requisite evolutions.

Executing tactical plans based upon faulted or inaccurate strategic insights and indicators has proven to be a common apparent cause in numerous case studies, after action reports and LODD reports. Our years of predictable fireground experience have ultimately embedded and clouded our ability to predict, assess, plan and implement incident action plans and ultimately deploy our companies-based upon the predictable performance expected of modern construction and especially those with engineered structural systems.

If you don’t fully understand how a building truly performs or reacts under fire conditions and the variables that can influence its stability and degradation, movement of fire and products of combustion and the resource requirements for fire suppression in terms of staffing, apparatus and required fire flows, then you will be functioning and operating in a reactionary manner, that is no longer acceptable within many of our modern building types, occupancies and structures. This places higher risk to your personnel and lessens the likelihood for effective, efficient and safe operations. You’re just not doing your job effectively and you’re at RISK. These risks can equate into insurmountable operational challenges and could lead to adverse incident outcomes. Someone could get hurt, someone could die, it’s that simple; it’s that obvious.

Considerations for changing fire flow rates, the sizing of hose line and the adequacies for fire flow demand and application rates, staffing needs for safe operations, considerations for defensive positioning and defensive operating postures must be considered, and it warrants repeating again; Reckless-Aggressive firefighting must be redefined in the built environment and associated with goal oriented tactical operations that are defined by risk assessed and analyzed tasks that are executed under battle plans that promote the best in safety practices and survivability within known hostile structural fire environments- with determined, effective and proactive firefighting

  • Doctrine of Combat Fire Engagement
    • Predictive Strategic Process
    • Tactical Deployment Model
    • Dynamic Tactical Deployment
    • Performance Indicators and Street Aides
      • Fire Dynamics
      • Resistance
      • Resilience
      • Structural Systems
      • Occupancy Hazard Profiles

The traditional attitudes and beliefs of equating aggressive firefighting operations in all occupancy types coupled with the correlating, established and pragmatic operational strategies and tactics must not only be questioned, they need to be adjusted and modified; risk assessment, risk-benefit analysis, safety and survivability profiling, operational value and firefighter injury and LODD reduction must be further institutionalized to become a recognized part of modern firefighting operations.

Aggressive firefighting must be redefined and aligned to the built environment and associated with goal oriented tactical operations that are defined by risk assessed and analyzed tasks that are executed under battle plans that promote the best in safety practices and survivability within known hostile structural fire environments.

Our current generation of buildings, construction and occupancies are not as predictable as past conventional or legacy construction and occupancies;

  • Risk assessment, strategies and tactics must change to address these new rules of structural fire engagement.
  • You need to gain the knowledge and insights and to change and adjust your operating profile in order to safe guard your companies, personnel and team compositions.
  • Again strategic firefighting operations; Strategies and tactics must be based on occupancy risk not occupancy type.

The following are quotes from Fire Chief Anthony Aiellos (ret) Hackensack (NJ) Fire Department, Fire Chief during the Hackensack Ford Fire, July, 1988…

“If you don’t fully understand how a building truly performs or reacts under fire conditions and the variables that can influence its stability and degradation, movement of fire and products of combustion and the resource requirements for fire suppression in terms of staffing, apparatus and required fire flows, then you will be functioning and operating in a reactionary manner. This places higher risk to your personnel and lessens the likelihood for effective, efficient and safe operations. You’re just not doing your job effectively and you’re at RISK. These risks can equate into insurmountable operational challenges and could lead to adverse incident outcomes”.

Engineered Structural Systems- Hazards

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600x6CNN recently presented an informative piece on the continuing trends in the design and use of engineered structural systems (ESS) . CNN correspondant Gerri Willis provides an informative and  insightful look at something the fire service knows all too well.  Here’s some additional information for you; According to the Wood Truss Council of America (WTCA), wooden trusses are used in roof systems in more than 60% of all buildings in the United States [SBCMAG 2004]. Truss and related engineered wooden floor systems are also becoming more common. Today, more engineered structures use lighter weight materials, producing larger spans and clear openings. Trusses can be designed to carry expected loads, be produced economically, be safely handled, and reduce construction costs.

Engineered building components may provide adequate strength under normal loading; but under fire conditions, these truss systems can become weakened and fail, leading to the collapse of roofs, floors, and possibly the entire structure. Truss systems are usually hidden, and fires within truss systems may go unnoticed for long periods of time, resulting in loss of integrity.

Structural design codes often do not factor in this decreased system integrity, as fire degrades the structural members. Fire fighters typically rely on warning signs to indicate imminent truss failure such as roofs and floors that feel spongy or are visibly sagging. Quite often, these warning signs are not good predictors of truss system failures. The United States Fire Administration (USFA) reports that during 1990-2000, structural fires and explosions accounted for 46.1% of all reported fire fighter fatalities (500 of 1,085) [USFA 2002].  Statistics compiled by the WTCA suggest that 4.7% of the total fatalities (108 of 2,286) during 1980-2001 were due to structural collapse [Grundahl 2003b]. Fifteen separate incidents investigated by NIOSH identified at least 20 fatalities and 12 injuries that have occurred from 1998-2003 during fire-fighting operations in buildings containing truss systems.

http://us.cnn.com/video/?/video/living/2009/12/18/willis.new.housing.fire.danger.cnn CNN Reports on ESS Dangers

At least three scenarios can occur in which fire fighters suffer fatalities and injuries while operating at fires involving truss roof and floor systems:
1. While fire fighters are operating above a burning roof or floor truss , they may fall into a fire as the sheathing or the truss system collapses below them.
2. While fire fighters are operating below the roof or floor inside a building with burning truss floor or roof structures , the trusses may collapse onto them.
3. While fire fighters are operating outside a building with burning trusses , the floor or roof trusses may collapse and cause a secondary wall collapse.

Building Construction Spring09 173

Truss and Engineered Systems Placards

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11-22-2008 9-05-24 PMThe Aldridge-Benge Firefighter Safety Act of 2008 became law on December 13, 2009 after unanimously passing the Florida House and Senate in 2008. The new law is named in honor of two Orange County, Florida  Firefighters, Todd Aldridge and Mark Benge, who died in 1989 after the roof of a gift shop collapsed; the bill is called the Aldridge-Benge Firefighter Safety Act. For a copy of the Act, HERE

 The Aldridge-Benge Firefighter Safety Act will require owners of any commercial, industrial, or any multi-unit residential structure, to mark these buildings in a manner that identifies them as light-frame truss-type construction. A sign or symbol will alert firefighters of the construction material and allow them to modify their tactics for fighting fires in buildings.

12-18-2009 9-58-41 AM

Aldridge-Benge Florida Placards

633.027 Buildings with light-frame truss-type construction; notice requirements; enforcement.

(1) The owner of any commercial or industrial structure, or any multiunit residential structure of three units or more, that uses light-frame truss-type construction shall mark the structure with a sign or symbol approved by the State Fire Marshal in a manner sufficient to warn persons conducting fire control and other emergency operations of the existence of light-frame truss-type construction in the structure.

(2) The State Fire Marshal shall adopt rules necessary to implement the provisions of this section, including, but not limited to:
(a) The dimensions and color of such sign or symbol.
(b) The time within which commercial, industrial, and multiunit residential structures that use light-frame truss-type construction shall be marked as required by this section.
(c) The location on each commercial, industrial, and multiunit residential structure that uses light-frame truss-type construction where such sign or symbol must be posted.

(3) The State Fire Marshal, and local fire officials in accordance with s. 633.121, shall enforce the provisions of this section. Any owner who fails to comply with the requirements of this section is subject to penalties as provided in s. 633.161

Truss Systems Placards For Firefighter Safety from across the United States. This was originally posted HERE . Check out the link for examples of various types of placards from various locations around the US. Additional Links HERE and HERE

- The Valley Independent Sentinel covers the proposed law in Derby, Can You Spare Five Dollars (To Save A Life)?.
- NFPA Journal: It’s not lightweight construction. It’s what happens when lightweight construction meets fire.
- Firehouse.com: Understanding the Dangers of Lightweight Truss Construction

-FireRescue1.com: Enhancing Firefigher SAfety, One Step at a time:

 New York State:  PDF HEREFR20Poster0320Large

The following represent various state or local level efforts that have been instituted to provide the fire service with identification placards for attachment to buildings constructed with truss support systems. What we don’t have is a unified national standard, nor do we have these systems in all states. The political strife and lobbying backed by special interest groups and mfg. associations that DO NOT Support these types of placard systems is appalling and inexcusable. This post is to make many of you aware of the various enhacements that exist to support firefighter safety.

New York State TRUSS TYPE CONSTRUCTION PlacardsNYS 19 NYCRR Part 1264 – IDENTIFICATION OF BUILDINGS UTILIZING TRUSS TYPE CONSTRUCTION
http://www.dos.state.ny.us/code/trussID.htm

More from New York State…..
http://www.trussid.org/index.html

City of San Francisco, CA
5.05 Signage of Buildings with Wood or Lightweight Steel Truss, or Composite Wood Joist (TJI) or Roof Construction
Reference: 2007 San Francisco Fire Code Section 507.3.2
http://www.sfgov.org/site/sffd_page.asp?id=80083

State of New Jersey TRUSS SIGNS (Truss Roof and Truss Floor Assembly Signs)
Exterior Placard NJAC 5:70 – 2.20(a)1 and 2 This attachment was provided by the New Jersey Division of Fire Safety and is referenced as Exterior Placard NJAC 5:70 – 2.20(a)1 and 2.
Truss roof signs are required by the New Jersey State Uniform Fire Code for buildings, which utilize either a floor or roof assembly consisting of truss construction. A truss sign gives early warning to fire and emergency service members that the roof and/or floor may be subject to early collapse in the event of a fire condition.

ISOSCELES TRIANGLE SIGNS
N.J.A.C. 5:70-2.20(a)1.
“The emblem shall be of a bright and reflective color, or made of reflective material. The shape of the emblem shall be an isosceles triangle and the size shall be 12 inches horizontally by 6 inches vertically. With letters of a size and color to make them conspicuous, shall be printed on the emblem, as shown in images below.”

N.J.A.C. 5:70-2.20(a)2
“The emblem shall be permanently affixed to the left of the main entrance door at the height of between 4 feet and 6 feet above the ground, and shall be installed and maintained by the owner of the building”.

NJtruss_signs

New Jersey Truss Placards

 

 

 

NIOSH Suggested Truss Placard Type
EXAMPLE LANGUAGE FOR A LAW REQUIRING LABELING OF BUILDINGS FOR THE FIRE SERVICE
This sample language is based on recommendations in the National Institute for Occupational Safety and Health (NIOSH) report entitled “NIOSH Alert: Preventing Injuries and Deaths of Firefighters due to Truss System Failures.”
The report states: “Consider placing building construction information outside the building. Include
information about roof and floor type.

The NIOSH report also recommends as part of pre-fire planning to: Record data regarding roof and floor construction (e.g., wooden joist, wood truss, steel joist, steel truss, beam and girder, etc.) [NFPA 2003]. The sample language below provides building labeling that identifies the building’s construction type, is simple yet logical, and should allow firefighters to quickly know the building’s floor and roof construction materials, promoting better and more complete information on the fireground and increased firefighter safety.

xxx Identification of structural construction. Structural construction types shall be identified by a sign or signs, in accordance with the provisions of this section.

xxx.1 Signs. Signs shall be affixed where a building or a portion thereof is classified as Group A, B, E, F, H, I, M, R-1, R-2, R-4 or S occupancy. The owner of the building shall be responsible for the installation of the sign.
xxx.2 New buildings and buildings being added to. Signs shall be provided in newly constructed buildings and in existing buildings where an addition that extends or increases the floor area of the building. Signs shall be affixed prior to the issuance of a certificate of occupancy or a certificate of compliance.

xxx.3 Existing buildings. Signs shall be provided in existing buildings. Signs shall be affixed within ninety days of being notified in writing by the Code Enforcement Official.

xxx.4 Contents of signs. Signs shall consist of a diagram 6 inches (152.4 mm)in height and width, with a stroke width of ¼ inch (6.4 mm). The sign background shall be reflective white in color. The diagram and contents shall be reflective red in color, conforming to Pantone matching system (PMS) #187. Where a sign is directly applied to a door or sidelight, it may be a permanent non-fading sticker or decal. Signs not directly applied to doors or sidelights shall be of sturdy, non-fading, weather resistant material.

xxx.5 Identification of construction classification. Signs shall contain the roman alphanumeric designation of the construction classification of the building, in accordance with the provisions for the classification of types of construction (types I through V) of the building code. The roman numeral designating construction classification shall be 1 inch (25.4 mm) minimum in height and have a stroke width of ¼ inch (6.4 mm) minimum, and it shall be reflective white in color on a background of reflective red.

xxx.6 Identification of year of construction. Signs shall indicate the building’s year of construction or major reconstruction. The arabic numeral indicating year of construction shall be 1 inch (25.4 mm) minimum in height and have a stroke width of ¼ inch (6.4 mm) minimum, and it shall be reflective white in color on a background of reflective red.

xxx.7 Identification of structural construction types. Signs shall contain the alphabetic designations identifying the structural construction types used in the building, as follows:

“W” shall mean sawn joist/rafter construction, wood members
“I” shall mean engineered I-joist construction, wood members
“S” shall mean steel construction
“T” shall mean truss type construction
“C” shall mean concrete construction

NIOSH Suggested Truss Placard

NIOSH Suggested Truss Placard

State of Florida, Truss Placard System 2008;
The Aldridge-Benge Firefighter Safety Act. The law was named in honor of Orange County firefighters Todd Aldridge and Mark Benge, who died in 1989 after the truss roof of a gift shop collapsed. Under the new law, owners of any commercial, industrial or multi unit residential structure, have to clearly mark if their buildings have lightweight roof or floor trusses, allowing firefighters to change their tactics when working in these types of structures

http://www.cfnews13.com/News/Local/2008/7/2/new_firefighter_protect….

633.027 Buildings with light-frame truss-type construction; notice requirements; enforcement
(1) The owner of any commercial or industrial structure, or any multiunit residential structure of three units or more, that uses light-frame truss-type construction shall mark the structure with a sign or symbol approved by the State Fire Marshal in a manner sufficient to warn persons conducting fire control and other emergency operations of the existence of light-frame truss-type construction in the structure.
(2) The State Fire Marshal shall adopt rules necessary to implement the provisions of this section, including, but not limited to:
(a) The dimensions and color of such sign or symbol.
(b) The time within which commercial, industrial, and multiunit residential structures that use light-frame truss-type construction shall be marked as required by this section.
(c) The location on each commercial, industrial, and multiunit residential structure that uses light-frame truss-type construction where such sign or symbol must be posted.
(3) The State Fire Marshal, and local fire officials in accordance with s. 633.121, shall enforce the provisions of this section. Any owner who fails to comply with the requirements of this section is subject to penalties as provided in s. 633.161.

Florida Placard

Florida Placard

 

Wheeling, Illinois Wood Truss Warning Signs
Attached is information from Wheeling, Illinois, who enacted thier own local code requriement. April 18, 1994 adopted Ordinance 2948 amending Title 14, Fire, of the Wheeling Municipal Code by adding Chapter 14.08 “Wood Truss Warning Signs”

State of Vermont
F or additional Info HERE

CITY OF CHESAPEAKE, VA TRUSS ID PROGRAM; A designated sticker is used for quick recognition of potential Collapse Dangers associated with TRUSS constructed buildings. The sticker is placed on every entry door of all commercial buildings with Truss construction. The use of trusses in building construction presents a great danger to firefighting personnel when those structures are involved in fire conditions. By design, the truss members in floor and roof assemblies will collapse, without warning, after being exposed to heat or flame contact for a very short period of time. Because of the inherent danger firefighters must face while operating within these buildings, a Truss Identification Program (TIP) has been instituted to alert personnel of the danger prior to beginning fire suppression operations. The Truss Identification Program is intended to alert the members of the Chesapeake Fire Department with pertinent pre-plan information before firefighting forces are committed to an interior attack.

The TIP shall be an ongoing program applied to all commercial buildings inspected by the Chesapeake Fire Department.
http://www.chesapeake.va.us/services/depart/fire/truss.shtml

City of Greencastle, Indiana

The City of Greencastle, Indiana and the Greencastle Fire Department recently enacted and approved an Engineered Lumber ID Program consisting of a sticker that is used for quick recognization of potential Collapse Dangers associated with Engineered Lumber constructed buildings. The sticker is placed on every electrical meter of all residential & commercial buildings with Engineered Lumber construction built after May 13th 2008. The news release states that; the use of this type of lumber in building construction presents a great danger to firefighting personnel when those structures are involved in fire conditions. By design, the Engineered Lumber in floor and roof assemblies will collapse, without warning, after being exposed to heat or flame contact for a very short period of time. Because of the inherent danger firefighters must face while operating within these buildings, an Engineered Lumber Identification Program (ELIP) has been instituted to alert personnel of the danger prior to beginning fire suppression operations.

The Engineered Lumber Identification Program is intended to alert the members of the Greencastle Fire Department with pertinent pre-plan information before firefighting forces are committed to an interior attack. The sticker is unobtrusive and is placed directly on a meter box, for example, and alerts the FD if either the floor joists and/or the trusses are made of and Engineered Lumber System and materials. The fire officers are already checking the utility boxes on all fires as part of their initial size-up. The ELIP shall be an ongoing program applied to all residential & commercial buildings inspected by the Greencastle Fire Department.

ORDINANCE 2008 – 4 states; AN ORDINANCE REQUIRING A REFLECTIVE SYMBOL ON STRUCTURES USING ENGINEERED LUMBER
WHEREAS, many new building structures currently use engineered lumber in their construction;
WHEREAS, some types of engineered lumber burn at a rate faster that other types of lumber; and
WHEREAS, in fighting fires, it would be helpful to know the types of materials used in the construction of a structure.

NOW THEREFORE be it ordained by the Common Council of the City of Greencastle as follows:
1. Definitions:
a. Engineered Lumber shall mean prefabricated I-joists, truss joists, and truss rafters, and laminated beams and studs.
b. Structure shall mean primary, secondary and accessory structures as defined in the Greencastle Zoning Code that have electrical meters that serve the structure.

2. All structures constructed with engineered lumber after the effective date of this ordinance must have a reflective symbol affixed to each electrical meter serving the structure.

3. The reflective symbol shall be in the form of a sticker, issued by the City of Greencastle that states that the structure is constructed with engineered lumber

4. Any person violating this ordinance by refusing to use the reflective symbol or by removing the reflective symbol shall be subject to a fine in an amount of $25.00 per violation. Each day that a violation occurs shall constitute a separate violation, subject to a separate fine.

5. The owner of any structure that was constructed with engineered lumber prior to the effective date of this ordinance is requested to place the reflective symbol on the electrical meter serving the structure on a voluntary basis.

This is another great example how local level insights, actions and legislation can go a long way in supporting fire service operational challanges as they relate to building construction systems, methodologies and materials. Remember, We can certainly work diligently AND cooperativley with local government officials to enhance incident operations and make our jobs safety, one step at a time….
For additional information on the Fire Department’s efforts in Greencastle, IN contact Lt. John Shafer, Lieutenant/Training Officer HERE.
 
An invaluable free on-line training program on Structural Stability of Engineered Lumber in Fire Conditions – is available from UL, check HERE for further information.
The 2006 NIOSH LODD Report, HERE

The New Lexicon and Challenges

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Floor TrussOf the many issues affecting the Fire Service, the prevailing challenge that has a pronounced impact on operational safety is the assimilation of engineered structural systems (ESS) into mainstream building design and construction. The presence of engineered structural systems (ESS) are no longer considered to be an innocuous feature in a given building or occupancy; it is the predominate feature in nearly all current construction, renovation and adaptive reuse or infill applications. It has become far more than just concerning ourselves with the presence of a simple light-weight or “engineered” truss roof system or a wood I-beam  floor assembly.

There is a new lexicon of building construction components and systems that must be added to your operational safety vocabulary and incident action plans. There is a new terminology, applications and a knowledge base to learn that will support operational excellence and support the integrity of incident safety performance of companies and personnel. Do you know what they represent and how these components, assemblies and systems may affect or influence an incident?

The fire service continues to apply the term “light weight construction” to a wide variety of building construction and systems. This expression has become a miss-application of both term and the correlation of risk and severity related to operational profiling. In other words, we apply and express the use of “light weight construction” for all types of engineered components, systems, designs and assemblies in nearly all types of building construction and occupancy use. Although the roots of the term can be traced back to the early 1980′s, and its application to the (then) emerging use of trussed roofing systems and the advent of wood I-beam floor supports (sans solid dimensional lumber joists), the use of the terminology in today’s context of risk assessment, strategic and tactical management and deployment models and within the context of incident operational tactics is no longer applicable, valid or suitable. It must be expanded into a more specific and descriptive level of classification and correlation.

For the most part, when discussing buildings and occupancies, aside from classifications related to code type or class as an element of fire resistance; the emphasis has been to differentiate between conventional and engineered construction, and the application of the term “light weight construction”. I continue advocating and promoting through my lectures that it’s much more than this when looking at the spectrum of construction and the structural anatomy of buildings. Current and past generations of buildings, construction and occupancies can be more accurately differentiated and classified within six (6) expanding categories in the following Building Construction Systems;

·        Heritage:              Pre-1900
·        Legacy:                1900-1949
·        Conventional:      1950-1979
·        Engineered:         1980-2009     Current into 2010…
·        Blended Hybrid:  1995-2009     Current into 2010…
·        Enigmatic:            2010-             Projected
 
We’ll discuss these six classifications in greater details in future postings here and expand the level of details on the CommandSafety.com and Buildingsonfire.com sites. Our current generation of buildings, construction and occupancies are not as predictable as past “conventional” construction, therefore risk assessment, strategies and tactics must change to address the advancement of new rules of combat structural fire engagement. But if you don’t understand or know what and how those changes in predictability have occurred, you may be operating with a false sense of operational risk and safety margin.

It’s a Lot More than just talking about “Light Weight” Construction….
·        From Plywood-CDX….to
·        Particle Board- PB…..to;
·        Orient Strand Board-OSB
·        Structural Composite Lumber- SCL
·        Laminate Strand Lumber- LSL
·        Laminate Veneer Lumber-LVL
·        Structural Insulated Panels-SIP
·        Parallel Strand Lumber-PSL
·        Machine Stress Rated Lumber- MSR
·        Medium Density Fiberboard-MDF and MDL (Lumber)
·        Finger Jointed Lumber-FJL
·        Adhesives…..
 
Do some research and check these terms out for starters. We’ll talk more about these components and assemblies in the near future. So get busy on your down time today over the next few days and discover the implications these components may have in your community….

Here’s a link to a past informative posting related to engineered systems and their relationship to firefighter safety and operations, HERE. There’s some great contributed information and manufacturer “insights” on the subject engineered wood I-joists and beams and firefighter safety. There are some interesting statistical extrapolations, correlations and conveniences’ that attempt to make the case. But then again, You be the judge. Take at look at the presentation developed by the American Forest and Paper Association, HERE and HERE.
 
If you haven’t done so yet, don’t forget to check out the free online training program on Structural Stability of Engineered Lumber in Fire Conditions at the UL University developed and provided by Underwriter’s Laboratories (UL),  HERE

Here’s a series of other important Reference Links that provide some insights on operational safety, incident conditions and factors and the lessons-learned from a number of LODD events;  

NIOSH Publication No. 2009-114: Preventing Deaths and Injuries of Fire Fighters Working Above Fire-Damaged Floors HERE

 NIOSH Publication No. 2005-132: Preventing Injuries and Deaths of Fire Fighters Due to Truss System Failures HERE

Volunteer Deputy Fire Chief Dies after Falling Through Floor Hole in Residential Structure during Fire Attack—Indiana, HERE

First-floor collapse during residential basement fire claims the life of two fire fighters (career and volunteer) and injures a career fire fighter captain – New York, Report HERE

Career Fire Fighter Dies After Falling Through the Floor Fighting a Structure Fire at a Local Residence – Ohio, HERE

Colerain Township, Ohio Double LODD Preliminary Report, HERE

Career engineer dies and fire fighter injured after falling through floor while conducting a primary search at a residential structure fire – Wisconsin, HERE

NFPA Report on Light Weight Construction, HERE

Informative USFA Coffee Break series postings related to Building Types & Fire Resistance:  HERE. HEREHERE, HERE, and HERE

Remember, Building Knowledge = Firefighter Safety (Bk-F2S)