Monthly Archives: August 2016

R. Thomas Long Jr. and Andrew F. Blum
Exponent, Inc., USA

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT
Fires involving cars, trucks, and other highway vehicles are a common concern for emergency responders. Between 2009 and 2011, there was an average of approximately 187,500 highway vehicle fires per year.  Fire Service personnel are accustomed to responding to conventional vehicle (i.e., internal combustion engine [ICE]) fires, and generally receive training on the hazards associated with those vehicles and their subsystems. However, in light of the recent proliferation of electric drive vehicles (EDVs), a key question for emergency responders is, “what is different with EDVs and what tactical adjustments are required when responding to EDV fires?”

The overall goal of this research program was to develop the technical basis for best practices for emergency response procedures for EDV battery incidents, with consideration for suppression methods and agents, personal protective equipment (PPE), and clean-up/overhaul operations. A key component of this project goal was to conduct full-scale fire testing of large format Lithium-ion (Li-ion) batteries as used in EDVs.

This article summarizes the full-scale fire tests performed, reviews the current emergency response tactics, and discusses what, if any, tactical changes relating to emergency response procedures for EDV battery incidents are required.

Download the complete paper here

On this day in (August 19) 1980, a fire aboard a plane bound for Saudi Arabia forces an emergency landing.

The Saudi Airlines flight began in Karachi, Pakistan, headed for Jidda, Saudi Arabia, with a stopover in Riyadh. The first leg of the flight was uneventful, and the Lockheed L-1011 took off from Riyadh with no problems. Shortly after takeoff from Riyadh, the pilot reported a fire onboard the plane and told air-traffic controllers that he needed immediate clearance to head back to the airport.

The fire started while passengers onboard were cooking with a portable butane stove. Apparently, this was not unusual, as Middle Eastern airlines are often willing to accommodate their Muslim passengers’ needs to follow the strict dietary laws of their religion. The pilot was able to land the plane back at Riyadh safely and headed to the end of the runway where a rescue crew was waiting.

When the plane reached the end of the runway, however, it burst into flames. The crew sprayed fire-fighting foam at the fire, but it was no match for the intense blaze. None of the 301 people onboard escaped the fire. It is still unclear why there were no survivors. Bodies were found piled up near the escape hatches. One theory is that panic on the plane caused a stampede that prevented the hatches from being opened. Another possibility is that the crew failed to depressurize the cabin, which would have prevented the hatches from opening. It is also possible that everyone on the flight was overcome by fumes before they could save themselves.

Source: History.com

Alfonso Ibarreta, Ph.D., PE, CFEI,
Timothy Myers, Ph.D., PE, CFEI, CFI,
James Bucher, Ph.D., CFEI and
Kevin Marr, Ph.D., CFEI
Exponent, USA

Presented at International Symposium on Fire Investigation, 2012

ABSTRACT

Natural gas, composed mainly of methane, is in some ways similar to propane gas. Both fuels have similar energy densities per unit mass, and similar laminar premixed flame burning velocities. However, propane explosions have been shown to produce higher overpressures in unconfined explosion tests when compared to methane. In vapor cloud explosion modeling, methane is considered to be a “low” reactivity fuel, while propane is listed as a “medium” reactivity fuel. In closed vessel explosion testing, the maximum rate of pressure rise for propane is almost twice than that for methane (based on KG  values reported in NFPA 68 (2007) Standard for Explosion Protection by Deflagration Venting , table E.1).

This study provides a direct comparison of the explosion severity between commercial propane and natural gas. Empirical correlations available for vented vessel explosions and unconfined Vapor Cloud Explosions (VCEs) are used to predict the difference in overpressure expected for a commercial propane explosion versus natural gas explosion. Although the maximum laminar burning velocity associated with propane is only about 15% higher than that associated with methane, commercial propane explosions are expected to result in overpressures that are about 40% higher than that of a natural gas explosion under identical conditions with a perfectly-mixed nearstoichiometric fuel-air mixture, based on empirical correlations.

In addition to the laminar burning velocity, other fundamental differences in the fuels may also play an important role in the explosion severity. Propane has a slightly higher expansion ratio than methane when undergoing combustion. The mass diffusivity of propane and methane are also quite different, making the premixed propane flame more prone to wrinkling under turbulent conditions. Future testing in the 20-L explosion chamber is suggested.

Download the complete paper here

Elizabeth C. Buc, PhD, PE, CFI
Fire and Materials Research Laboratory LLC

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT

Under some conditions, chemicals that are otherwise stable can react, evolve heat and cause a fire, detonate or explode. The fire investigator has to identify the chemical reactants, the reaction products and conditions that supported ignition and flame spread. A chemical fire investigation flow diagram and real-world examples of fires involving chemicals are presented to assist the fire investigator in processing chemical fires. Examples of chemical fires include self-heating, a thermite reaction, a runaway reaction from mixing incompatible materials and reactions generating hydrogen gas. Factors contributing to chemical fires such as size or quantity of material, confinement, contamination and upset process conditions are identified. Sampling, chemical analyses, literature review, and/or testing proposed or potential adverse chemical reactions are required to establish the root cause of a chemical fire.

Download the complete paper here

A coal-mine fire kills 262 workers in Marcinelle, Belgium on August 8, 1956. This highly publicized disaster was the worst ever in a Belgian mine and led to many policy changes.

The disaster itself was typical of coal-mine tragedies. An accident began at 8:10 AM when the hoist mechanism in one of the shafts was started before the coal wagon had been completely loaded into the cage. Electric cables ruptured, starting an underground fire within the shaft. The moving cage also ruptured oil and air pipes which made the fire worse and destroying much of the winch mechanism. Smoke and carbon monoxide spread down the mine, killing all the miners trapped by the fire. With the families of the miners waiting aboveground at the scene, it was not until August 23—more than two weeks later—that rescue workers could reach the deepest level of the mine. Reportedly they said, “tutti cadaveri” immediately, which is Italian for “all corpses.”

The rescue workers were speaking Italian because the majority of workers at the Le Bois du Cazier mine were Italian. At the time, Belgium was experiencing a labor shortage and had made agreements with Italy to trade work visas for coal. The tragic fire resulted in 136 Italian workers losing their lives; the immigration agreement between the two countries was terminated immediately. Despite an attempted rescue from the surface, only 13 of the miners who had been underground at the time of the accident survived. 262 were killed, making the mining accident the worst in Belgian history.

Belgium also called a conference on safety in coal mines in the aftermath of the disaster. In September 1956, the Mines Safety Commission was established. It was charged with monitoring safety procedures and developing new regulations. The country’s prompt response to the disaster led to much improved safety in Belgian and other European mines.

Source: History.com and Wikipedia.com
Photo from: MinedHistoires.org 

Gerald A. King, J.D., CFEI
Armstrong Teasdale LLP, USA

Karrie J. Clinkinbeard, J.D., CFEI
Armstrong Teasdale LLP, USA

Presented at International Symposium on Fire Investigation, 2012

ABSTRACT

Both federal and state courts require experts to employ reliable scientific methodologies. Various jurisdictions employ different factors in determining whether an expert’s methodology is scientifically reliable. For years, courts have excluded unreliable expert testimony in fire litigation, an issue previously the subject of Experts Beware: Ignoring the Scientific Method Can Be Hazardous to Your Testimony , an article and presentation included in the ISFI 2010 Proceedings.

Despite the fact that the courts and NFPA 1033, the Standard for Professional Qualifications for Fire Investigators, require fire investigators to employ all elements of the scientific method as the operating analytical process throughout the investigation and for the drawing of conclusions, experts still fail to utilize the scientific method to ensure the reliability of their opinions. Some experts still believe that they can ignore the scientific method by claiming NFPA 921 is only a guide. Although many courts cite NFPA 921 as the “industry standard” for judging an expert’s methodology, other courts exclude experts for the failure to follow the principles articulated in NFPA 921 without ever citing to NFPA 921. An expert’s claim that NFPA 921 is “only a guide” does not relieve the expert from demonstrating that the chosen methodology is scientifically reliable. The legal standards governing the admissibility of an expert’s opinion demand a scientifically reliable methodology. Ignoring the principles set forth in NFPA 921 can and with almost certainty will result in exclusion  of an expert’s opinions (in whole or in part) and open an expert to the risk of third party lawsuits.

This article provides an updated look at these issues and analyzes recent cases where an expert’s testimony has been excluded in fire litigation and, in some instances, the expert has been sued for these deficiencies. Experts are excluded for ignoring facts or relying upon speculative facts. There is a trend towards excluding experts who do not test their ignition theory, particularly in product liability cases. The common theme in these cases continues to be that the expert ignored a step in the scientific method and, therefore, the opinions are unreliable and inadmissible.

Download the complete paper

1933, Aug 14:  Logging accident sparks forest fire in Oregon Coast Range

On August 14, 1933, a devastating forest fire is sparked in the Coast Range Mountains, located in northern Oregon, 50 miles west of Portland. Raging for 11 days over some 267,000 acres, the blaze began a series of fires that struck the region at six-year intervals until 1951 that became known collectively as the Tillamook Burn.

The first Tillamook Burn fire—which began around noon on August 14, 1933—was sparked in a logging operation located on the slopes above the North Fork of Gales Creek, west of the town of Forest Grove. An official investigation of the fire found that it stemmed from friction produced when loggers dragged a large Douglas-fir log across a downed tree, igniting a large amount of logging debris in the area. Weather conditions—including an unusually high temperature of 104 degrees Fahrenheit, with only 20 percent humidity—helped ignite and spread the blaze, and within an hour, the fire had destroyed 60 acres of the surrounding land.

Present-day roads and highways in the region had not yet been built, and the remote location of the logging operation meant that the loggers were forced to fight the fire largely by themselves. Some 3,000 men, including loggers, local farmers and volunteers and several hundred members of the Depression-era Civilian Conservation Corps, battled with the fire over 10 days as it burned through some 40,000 acres. On the night of August 24, strong east winds spread the blaze over 240,000 more acres in only 20 hours, making it one of the fastest-growing forest fires of the 20th century.

Though its spread was eventually stopped by rain, the devastation caused by the blaze primed the region for future forest fires. In 1939, another fire raged over more than 200,000 acres of the Coast Range, including 19,000 acres of previously untouched forest. In 1945, two fires burned 182,000 acres, and in 1951, another two fires consumed more than 32,000 more. All told, the fires of the Tillamook Burn damaged or destroyed a combined total of 355,000 acres (554 square miles) of the country’s richest timberland.

In the years after 1951, much of the land in the Coast Range began moving from private to public ownership, as struggling landholders forfeited their property to the government rather than pay property taxes on the damaged land. With the land under state control, the legacy of the Tillamook Burn continued to shape life in the region for decades to come, as the Oregon Department of Forestry launched comprehensive fire-protection and reforestation programs, including the planting millions of seedlings by hand and via helicopter.

Source: History.com

Scott Nesvold, M.S., M.Eng., P.E.
Crane Engineering Building Science, USA
and
Kerri Pacholke, MFS, F-ABC
Crane Engineering, USA

Presented at International Symposium on Fire Investigation, 2012

ABSTRACT

In a recent fire investigation, a vehicle owner claimed an accidental fire had destroyed his vehicle. An observant fire investigator, who suspected arson based on the facts of the case, found a small pile of “white residue” and some other parts in the debris and sent the residue to a lab to be analyzed. Fourier Transform Infrared Spectroscopy (FT-IR) was conducted as a presumptive test and revealed the presence of Strontium, a common chemical found in road flares. The presence of a high concentration of Strontium was confirmed using a Scanning Electron Microscope (SEM) combined with an Energy Dispersive X-ray Spectroscopy (EDS) unit. Based on the evidence and this analysis, the residue was confirmed to be from a road flare. The vehicle fire was determined to be incendiary based on this analysis.

A test burn was conducted in a furnished condemned house. The house was burned room by room for fire investigator training. One fire was ignited in a furnished living room with a red road flare placed at the leg of a couch. The room was allowed to burn post-flashover for several minutes. Normal suppression and overhaul was performed by the firefighters on the scene. On the following day, a team of fire investigators was asked to determine the source of ignition. The flare residue remained and was visible in the area of origin, but was not discovered or identified by the team of investigators assigned to that particular room.

The testing required to identify flare residue is not included during standard ignitable liquid residue (ILR) tests. Traditional analysis performed on fire debris is for the presence of ILRs which are organic and volatile. Road flare residues are solid and inorganic and therefore, are not detectible using these standard examination techniques.

The residue that remains after burning a road flare is a whitish-grey solidified pool. The color and texture of the white material blends well with gypsum wallboard or plaster fragments typically found after post-flashover fires or fire department overhaul procedures and is therefore easily overlooked. Other components of a road flare may also be present including a cap, wooden plug, metal nail, wire legs, a base or possibly the remains of the cardboard tube.

Road flares are widely available for purchase, and are often included in a typical roadside safety kit. This widespread availability, high burn temperature (1450 °C, 2650 °F) and high heat release rate lends itself as a ready ignition source for incendiary fires. Due to the extended burn times of some road flares, they can be used to delay the start of an incendiary fire which may allow an alibi to be established.

Historically, minimal research has been performed on the role of road flares in incendiary fires. This research investigates the chemical signatures present following a fire that positively identifies the presence of road flare residue. It will also evaluate the remaining components and residue and visual burn patterns that occur when road flares are placed in proximity to common construction materials (such as gypsum wall board, carpet, plywood subfloors, etc.). Finally, it examines the remaining components and residue following vehicle fires.

NFPA 921 requires that the source of ignition, first fuel and the circumstances or conditions which brought them together be identified. The purpose of this research is to assist fire investigators in identifying the possible remains of a road flare during a fire investigation and explain the methods used to confirm the presence of a road flare through FT-IR and SEM-EDS analysis.

Download the complete paper