Analysis of Post-Fire Characteristics of Portable Oil Filled Room Heaters

Analysis of Post-Fire Characteristics of Portable Oil Filled Room Heaters to Determine Pre-Fire Orientation

K. Scott Barnhill, PE
Investigative Forensic Specialists, PLLC

Presented at the International Symposium on Fire Investigation Science and Technology, 2014

ABSTRACT
A portable oil filled room heater is a steel vessel typically with 5 to 8 fins containing approximately 3 to 4 liters of mineral oil. The mineral oil acts as the heat transfer fluid that is heated by an immersed electric heating element. The outward appearance of an oil filled heater is that of an old steam radiator.

An oil filled heater (OFH) exposed to full room involvement conditions will commonly display fire effects to include: rupture of the vessel’s spot welds, localized wavy deformations to the fins in the unwetted regions of the vessel, and differential deformation of the vessel’s fins. This study addresses the post-fire characteristics of oil filled heaters exposed to full room involvement conditions in two burn cells. A primary focus of the study is to determine if the pre-fire orientation of the oil filled heater can be determined by analysis of the post-fire appearance. A description of the dynamics that occur between the wetted and unwetted surfaces when the vessel is exposed to full room involvement conditions is discussed.

Analysis of an OFHs’ post-fire characteristics, to include vessel dimensions and wavy deformations, compared to the burn cell experiment results, allows an investigator to accurately interpret the normal reaction of an OFH to full room involvement as well as to determine its pre-fire orientation (upright or otherwise).

Download the complete paper here


Arc Mapping as a Tool for Fire Investigations

There has been a lot of debate in fire investigation industry recently regarding Arc Mapping.  NAFI’s mission is to increase the knowledge and improve the skills of persons engaged in the investigation and analysis of fires, explosions and arsons, or the litigation that ensues from such investigations. The opinions expressed in this paper do not necessarily reflect the opinion and beliefs of NAFI. Over the next three weeks, we will be sharing different views on Arc Mapping with our members and the industry – it is up to you to draw your own conclusions.

Week 1 – Arc Mapping: New Science or New Myth?
Week 2 – Arc Mapping as a Tool for Fire Investigations

ATF Fire Research Laboratory Technical Bulletin
Arc Mapping as a Tool for Fire Investigations

ABSTRACT
The purpose of this Technical Bulletin is to address statements that are contained in Arc Mapping: New Science or New Myth?, which was presented at the Fire and Materials Conference in February 2017. The paper’s interpretations and analysis of the published literature, the limitations it places on the process of arc mapping, and the conclusion that arc mapping is applicable to less than 1% of fire scene investigations are misleading. This bulletin addresses some of these issues.

Download the entire technical bulletin here.

 


St. John’s School Fire – October 28, 1915

The St. John’s School fire was a deadly fire that occurred on the morning of October 28, 1915, at the St. John’s School on Chestnut Street in the downtown area of Peabody, Massachusetts. Twenty-one girls between the ages of 7 and 17 were burned or crushed to death while attempting to escape the fire.

More than 600 children were in the building when the fire began in the basement of the school building. There were no fire escapes on the outside of the building, but instead those inside were forced to use wide stairways at either end of the interior which led down to the front exit. Mother Superior Aldegon, who led the Sisters who taught in the Catholic school, sounded a fire alarm and began the routine fire drill procedure.

This procedure should have led to the children and teachers leaving the building through the stairways to and out of a rear exit. However, as smoke thickened and the fire came closer, they ran for the front door instead, and became jammed in the vestibule. The fire broke through to the vestibule from directly under the front entrance and the vestibule, now crowded with pupils, was enveloped in flames. The fire rapidly swept through the three-story brick and wooden building, fully engulfing it in less than five minutes.

With their exit blocked, many of the children escaped through first-floor windows or jumped from those on the second and third floors. Not all were able to escape, however; the bodies of the 21 victims were found after the fire subsided, huddled together and burned beyond recognition, on the inside of the school entrance. The Sisters of Notre Dame who taught at St. John’s aided the children trying to escape, some by dropping the students into coats and blankets being used as life nets. These actions were credited in saving many lives. Two of the nuns were injured, one suffering serious burns; however, none of the adults were killed.

As a result of this fire, Peabody became the first city to pass a law that said all doors (in public buildings and school) must push out.

Source: Wikipedia


Reduced Scale Enclosure Testing with Low Heat Release Initial Fuel Packages

Mark A. Campbell, CFPS, SET
Wheat Ridge Fire Protection District, USA

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT

The scientific method is the process in which the fire investigator, among other steps, develops a hypothesis and tests it. The 2011 NFPA 921, §20.5.1, states that “Fire testing is a tool that can provide data that compliment data collected at the fire scene (see 4.3.3), or can be used to test hypotheses (see 4.3.6). Such fire testing can range in scope from bench scale testing to full-scale recreation of the entire event.” (bold and italics added). A Full Scale Enclosure (FSE) testing of a hypothesis may be quite expensive, time consuming, and just not practical. Building and burning a Reduced Scale Enclosure (RSE) may provide insight into the various fire effects, patterns, and dynamics within the enclosure.

Previous FSE burns at Eastern Kentucky University examined the results of a low heat release rate initial fuel source and how the area of origin, based upon the fire effects and fire patterns, preserved through post flashover. This paper will discuss current research on the same concept but with the RSE (1/4 scale). Through the use of the applicable scaling laws, low heat release rate initial fuels were designed and applied to various locations on and around the furniture. The RSEs were burned two minutes post flashover. In all four test burns the areas of origin were determined based upon the collective fire effects and fire patterns. These results have demonstrated that the RSE, when applying the scaling laws appropriately, are a very useful tool for fire investigator and fire protection engineers.

Download the complete paper here.


Distinguishing Between Arcing and Melting Damage

DISTINGUISHING BETWEEN ARCING AND MELTING DAMAGE IN ELECTRICAL RECEPTACLES

Matthew Benfer and Daniel Gottuk
Hughes Associates Inc., USA

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT

The majority of fire-investigation related literature on electrical arcing focuses on copper wiring, both stranded and solid, with some attention paid to steel (i.e., conduit), and relatively little mention of brass. This is despite the relatively equal presence of copper, steel, and brass in receptacles and similar electrical devices. Changes to NFPA 921 in the 2014 edition of the guide expand upon the characteristic traits which can be used to assess whether arcing or melting is present in a conductor. However, most of the characteristic traits of arcing and melting are qualitative and not well defined in NFPA 921, which leads to more subjective evaluations. In addition, a myopic examination of evidence with respect to the presence of one or two characteristic traits can lead to a false indication of arcing. In cases such as this, other evidence of melting (i.e., in close proximity to the area in question) could preclude confirmation of arcing.

The purpose of this work was to determine which characteristic traits are effective in assessing potential arcing damage on receptacle components and wiring. A total of 86 receptacles were evaluated in this study. Thirty-nine receptacles failed as a result of an overheating connection resulting in arcing damage; this included 95 individual conductors. Forty-seven receptacles with fire-induced arcing were also evaluated; this included 87 individual conductors. All of the evaluated receptacles with fire-induced arcing were energized or energized with a load during testing. In contrast, thirty-seven non-energized receptacles with fire induced melting were evaluated with 57 individual conductors.

The characteristic arcing traits which were evaluated include: corresponding damage on the opposing conductor; localized point of contact with a sharp line of demarcation between undamaged and damaged areas; round, smooth shape; resolidification waves; tooling marks visible outside the area of damage; internal porosity; spatter deposits; and small beads and divots over a limited area. The characteristic traits of melting which were evaluated include: visible effects of gravity; gradual necking of the conductor; and pitting, thinning, and presence of holes in the conductor. These traits were taken from the literature (e.g., NFPA 921) and from observations made during the forensic examinations of receptacles and wiring conducted as part of this work. For each characteristic, there were three possible outcomes: Yes, No, and Possible. Yes indicated that the characteristic was judged to be present on the particular conductor; no indicated that the characteristic was judged not to be present on the conductor. Possible indicated that confirmation could not be made either for or against the presence of the characteristic. All of the evaluations were conducted by the same person.

Corresponding damage on the opposing conductor, localized damage with a sharp line of demarcation, and tooling marks outside of the area of damage were observed on significant portions of arc damaged conductors and small numbers of conductors with melting damage; these characteristics were found to be strong indicators of arcing.

Using multiple characteristic traits and contextual information for determination of arcing vs. fire-melting provides greater confidence in the evaluation of damage. In addition, visual examinations were found to be reliable indicators of both arcing and fire-melting for most conductors. However, there are some cases which would benefit from more advanced examination techniques including SEM/EDS examinations, X-ray, CT scanning (X-ray computed tomography), cross-sectioning and polishing, or other metallurgical methods.

Download the complete paper here.


Anatomy of a Wrongful Arson Conviction

ANATOMY OF A WRONGFUL ARSON CONVICTION: SENTINEL EVENT ANALYSIS IN FIRE INVESTIGATION

Paul Bieber, CFEI, B.S., M.L.S. The Arson Research Project

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT

Anatomy of a Wrongful Arson Conviction will discuss the first comprehensive review of U.S. arson exonerations and the first application of sentinel-event and root-cause analysis to the field of fire investigation. Its purpose is to expose and explain the common factors that contribute to wrongful arson convictions.

Sentinel-event analysis has been embraced by several industries as an objective method of identifying and explaining the root causes of errors that have led to harmful outcomes. By reviewing dozens of arson cases, the Arson Research Project has documented the common errors at the heart of many fire investigations where accidental, natural or undetermined fires have been misidentified as arson.

This paper will also highlight the presence and impact of various forms of cognitive bias in each case study and emphasize the importance of objectivity and independence in the reliable application of the scientific method.

The 27 cases being reviewed include 19 exonerations, 7 cases where charges were dropped or a jury returned a not- guilty verdict, and one case that resulted in an execution. Together they represent over 200 years of combined incarceration and several life sentences. Even in the cases where the defendant was acquitted or the charges were dropped, the financial cost and emotional toll to the wrongfully accused were enormous. It is only through a clear examination and better understanding of these common errors that we may hope to avoid similar errors. This case- study review will attempt to shed some light on the problem in an ongoing effort to improve the practice of fire investigation and avoid future wrongful arson convictions.

Download the complete paper here.


1904, June 15th:  River excursion ends in tragedy

More than 1,000 people taking a pleasure trip on New York City’s East River are drowned or burned to death when a fire sweeps through the boat. The General Slocum disaster was the New York area’s worst disaster in terms of loss of life until the September 11, 2001 attacks. It is the worst maritime disaster in the city’s history, and the second worst maritime disaster on United States waterways.

The riverboat-style steamer General Slocum was built in 1890 and used mostly as a vehicle for taking large groups on day outings. On June 15, the St. Mark’s German Lutheran Church assembled a group of 1,360 people, mostly children and teachers, for their annual Sunday School picnic. The picnic was to take place at Locust Point in the Bronx after a cruise up the East River on the General Slocum.

At about 9 a.m., the dangerously overcrowded boat left its dock in Manhattan with Captain William Van Schaik in charge. As the boat passed 83rd Street, accounts indicate that a child spotted a fire in a storeroom and reported it to Captain Van Schaik. Reportedly the captain responded, “Shut up and mind your own business.” But as the smoke became more obvious, crew members were sent to investigate. By this time, the storeroom, filled with a combination of oil and excelsior (wood shavings used for packing), was blazing out of control. The onboard fire hose, which had never been used, tested or inspected, did not work.

Captain Van Schaik made a fateful decision at this time. Instead of directing the boat to the nearest dock where firefighters could engage the fire, he pointed the boat toward a small island in the East River. He later told investigators that he did not want to risk spreading the fire to the dock and the rest of the city, but the strategy proved deadly for the passengers. Instead of grounding the boat on the sand, the boat crashed onto the rocks of the island’s shore.

At this point, other factors also combined to exacerbate the situation. The lifeboats were so firmly tied to the steamer that they could not be released. The life preservers had not been filled with cork, but a non-buoyant material that made them weighty. The children who used them sank to the bottom of the river. Other children were trampled to death in the panic. More people were killed when the raging fire collapsed some of the decks, plunging them into the fire.

In all, 630 bodies were recovered and another 401 were missing and presumed dead. A cannon was brought to the scene and fired over the river the next day to loosen bodies from the river mud. The boat’s crew, and officers in the Knickerbocker Company, owner and operator of the General Slocum, were charged with criminal negligence. However, only Captain Van Schaik received a prison sentence. He was supposed to serve 10 years, but was pardoned due to old age in 1908. President Theodore Roosevelt fired the chief inspector of the U. S. Steamboat Inspection Service in the aftermath of the accident; wholesale changes in the industry followed. A mass grave was set up in Queens for the victims and a yearly memorial was held to honor their memory.

Source: History.com
Image: The Library of Congress – shows the mass of burned timbers and ruined metal, showing broken paddle wheels shaft.


May 6, 1937:  Hindenburg explodes in New Jersey

On this day in 1937, the German airship Hindenburg, the largest dirigible ever built, explodes as it arrives in Lakehurst, New Jersey. Thirty-six people died in the fiery accident that has since become iconic, in part because of the live radio broadcast of the disaster.

The dirigible was built to be the fastest, largest and most luxurious flying vessel of its time. It was more than 800 feet long, had a range of 8,000 miles, could carry 97 passengers and had a state-of-the-art Mercedes-Benz engine. It was filled with 7 million cubic feet of hydrogen, even though helium was known to be far safer, because it made the flying ship more maneuverable.

The Hindenburg had made 10 successful ocean crossings the year before and was held up by Germany’s Nazi government as a symbol of national pride. Flying at a speed of 85 miles per hour, the Hindenburg was scheduled to arrive in New Jersey at 5 a.m. on May 6. However, weather conditions pushed the arrival back to the late afternoon and then rain further delayed the docking at Lakehurst. When the dirigible was finally cleared to dock, Captain Max Pruss brought the ship in too fast and had to order a reverse engine thrust. At 7:20 p.m., a gas leak was noticed. Within minutes, the tail blew up, sending flames hundreds of feet in the air and as far down as the ground below.

A chain reaction caused the entire vessel to burn instantly. The nearly 1,000 spectators awaiting the Hindenburg‘s arrival felt the heat from a mile away. Some on the blimp attempted to jump for the landing cables at the docking station but most died when they missed. Others waited to jump until the blimp was closer to the ground as it fell. Those who were not critically injured from burns often suffered broken bones from the jump. Fifty-six people managed to survive.

On WLS radio, announcer Herbert Morrison gave an unforgettably harrowing live account of the disaster, “Oh, oh, oh. It’s burst into flames. Get out of the way, please . . . this is terrible . . . it’s burning, bursting into flames, and is falling . . . Oh! This is one of the worst . . . it’s a terrific sight . . .oh, the humanity.”

Source: History.com


Aluminum Phosphide-Based Fumigants as an Ignition Source

ALUMINUM PHOSPHIDE-BASED FUMIGANTS AS AN IGNITION SOURCE IN AGRICULTURAL COMMODITY STORAGE STRUCTURE FIRES

John L. Schumacher, MChE, PE, CFI, CFPS
Zachary J. Jason, PE, CFEI
Advanced Engineering Investigations Corporation, USA

Presented at International Symposium on Fire Investigation, 2012

ABSTRACT

Raw agricultural commodities, such as corn, soybean, rice and wheat, are typically stored in bins and silos prior to shipment. During storage, it is often necessary to protect the commodities from damage by insects and pests. A common protection method utilized is the addition of solid fumigant pellets or tablets to the commodity.

One of the most common solid fumigants employed is a blend of aluminum phosphide, ammonium carbamate and other inert ingredients. Aluminum phosphide reacts with atmospheric water and moisture in the commodity based on the following equation:

AlP + 3H2O = Al(OH)3 + PH3 + Heat

The reaction yields phosphine gas (PH3), which is highly toxic to insects, pests and humans. The reaction is exothermic, which means heat is generated alongside the other products. Phosphine gas has a lower flammable limit (LFL) of about 1.8% gas in air and can ignite spontaneously at concentrations above the LFL. The ammonium carbamate is added to the mixture to reduce the potential fire hazard by generating ammonia and carbon dioxide, which act as inerting gases. The carbon dioxide reduces the tendency of phosphine to auto-ignite in air. The decomposition reaction is as follows:

NH2COONH4 = 2NH3 + CO2

Improper application of the fumigant tablets or pellets can lead to fires. This paper provides basic product information, and discusses the chemistry, application methods, previous testing, and ignition scenarios associated with solid fumigants containing aluminum phosphide. A case study of a fire that occurred in a metal grain bin containing wheat will be presented.

Presented at International Symposium on Fire Investigation, 2012


Apr 27, 1865: Civil War vets are caught in steamboat explosion

On April 27 in 1865, an explosion on a Mississippi River steamboat kills an estimated 1,547 people, mostly Union soldiers returning home after the Civil War. Although this disaster near Memphis took a huge toll, it was barely noticed against the backdrop of the end of the Civil War, a conflict in which tens of thousands had died.

The previous day had marked the final surrender and end of armed resistance by the remaining Confederate forces. Only two weeks earlier, President Abraham Lincoln had been assassinated. Prisoners of war who had been held in hellish conditions in Alabama’s Andersonville and Cahaba prison camps were trying to make their way home to Illinois. The steamboat Sultana was one of their only options.

At 2 a.m. on April 26, the steamboat left Vicksburg, Mississippi. It was built to hold 376 passengers, but reports say that there were as many as 2,700 people on board as it lumbered slowly up the Mississippi River. It took 17 hours to make the journey to Memphis, where it stopped to pick up more coal.

A couple of hours past midnight, the trip came to a sudden end: near the Arkansas side of the river, one of the Sultana’s three boilers suddenly exploded. Hot metal debris ripped through the vessel and two other boilers exploded within minutes of the first. The passengers were killed by flying metal, scalding water, collapsing decks and the roaring fire that broke out on board. Some drowned as they were thrown into the water, but rescue boats were immediately dispatched, saving hundreds of lives.

The final tally of casualties was hotly disputed. Some believe it may have been almost 2,000 people, though the U.S. Army said that only 1,200 people had been killed. Local customs officials determined that 1,547 were killed; that became the generally accepted count. The Sultana disaster remains one the most deadly maritime accidents in U.S. history.

Source: History.com
Image: Library of Congress