Fires Involving Air Conditioning Fan Coil Units

Lim Beng Hui, M.Sc(FI)(Dist), B.Eng(Civil)(Hons), CFEI, CFII Singapore Civil Defence Force, Singapore

Yazeed Abdul Rahman, B.Eng(EEE)(Hons), CFEI, CVFI
Singapore Civil Defence Force, Singapore

Soh Seok Yuen, B.Eng(Mech)(Hons)
Singapore Civil Defence Force, Singapore

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT
Air conditioning is common in Singapore households due to the hot and humid tropical weather all year round. The typical air conditioning found in Singapore homes is the multi-split system which comprises a condensing unit (CU) and a number of wall-mounted fan coil units (FCU). From 2008 to 2013, there were 168 reported multi-split air conditioning fires of which 74 involved the wall-mounted FCU.

Fires involving the wall-mounted FCU are of greater concern than fires involving other parts of the multi split system as they have the propensity to cause significant property damage. There is also a lack of awareness on such fires in some local communities.

This paper details the observations made in a study on fires involving the multi-split air conditioning system in Singapore from 2008 to 2013. The intent of this study is to present investigative evidence that wall-mounted FCU fires can happen. The study also seeks to debunk the myth that wall-mounted FCU fires cannot happen when the FCUs are on standby mode. Additionally, the study will discuss how the burn patterns can possibly mislead investigators and highlights the value in scrutinising fires which are localized to the wall-mounted FCU.

Download the complete paper


Constantinople fire, 1870

A huge section of the city of Constantinople, Turkey, is set ablaze on June 5 in 1870. When the smoke finally cleared, 3,000 homes were destroyed and 900 people were dead.

The fire began at a home in the Armenian section of the Valide Tchesme district. A young girl was carrying a hot piece of charcoal to her family’s kitchen in an iron pan when she tripped, sending the charcoal out the window and onto the roof of an adjacent home. The fire quickly spread down Feridje Street, one of Constantinople’s main thoroughfares.

The Christian area of the city was quickly engulfed. There was a high degree of cooperation among the various ethnic groups who called the city home, but even this was no match for the high winds that drove the rapidly spreading fire. An entire square mile of the city near the Bosporus Strait was devastated. Only stone structures, mostly churches and hospitals, survived the conflagration.

In 1887, Edmondo de Amicis published perhaps the best account of this disaster in a book called Constantinople.

Source: History.com


The Anatomy of a Marine Fire Investigation

Christopher J. Reed, CFEI, MIFireE, MSc.Eng (Fire), P.Eng,
Sereca Fire Consulting Ltd., British Columbia, Canada

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT
Fires occurring in marine environments present the fire investigator with unique challenges. The nature of the marine environment presents an immediate safety hazard and introduces complications in suppression, scene documentation, and evidence contamination. As the scene can sink or become submerged, fire patterns are obscured and evidence can be lost, contaminated, or otherwise dispersed. Because the fire may occur in remote areas, within boathouses or in close proximity to other boats, additional fuel, the environment, and suppression tactics can further limit the investigator’s ability to identify causation factors.

Overall, the general site conditions, construction materials, and the specific electrical and mechanical systems leaves the investigator wading through collapsed structures and sunken vessels, endless piles of burned fiberglass, congealed plastics and melted aluminum, and a disarray of electrical, fuel, and mechanical systems all potentially compromised further by salt water and oxidation not related to the fire. The interpretation of fire patterns is further complicated by specific ventilation effects, fuel loads in different areas of the vessel, and the unusual progression of the fire as it is obstructed or contained by bulkheads in the cabins and hull. The combination of lightweight materials and the influence of venting from open hatches, port lights, or passageways can create fire patterns that could mislead the investigator from the true origin and cause.

This paper examines the process of conducting a marine fire investigation from securing sunken vessels to evaluating common ignition scenarios in vessels and land based associated facilities. Investigation methodologies outlined in NFPA 921 (2014) are reviewed and common failure modes of the various systems are categorized with characteristic fire damage to assist in cause determination.

Download the complete paper


The most deadly lightning strike in history?

On June 26 in 1807, lightning hits a gunpowder factory in the small European country of Luxembourg, killing more than 300 people. Lightning kills approximately 73 people every year in the United States alone, but victims are almost always killed one at a time. The Luxembourg disaster may have been the most deadly lightning strike in history.

The earth experiences 8 to 9 million lightning strikes every single day. In a typical year, the United States will see about 70,000 thunderstorms somewhere in its territory. This produces approximately 20 million lightning strikes annually. A bolt of lightning can reach 50,000 degrees Fahrenheit in instant heat. There are 100 million volts in an average lightning bolt, which can be as much as five miles long.

In 1807, Luxembourg was occupied by Napoleon’s army. The French dictator used the country to stockpile weapons and ammunition. Many underground bunkers were built for this purpose.  In the southern Luxembourg city of Kirchberg, a fortress built in 1732 was used as an armory.

When lightning struck the fortress on June 26, the ammunition housed within ignited on contact, causing a massive explosion. Two entire blocks were completely razed by the blast, which caused several other fires to rage nearby.  The London Times later reported, “This city has been plunged into the greatest consternation and distress.”

Source: History.com


The 1875 Liberties Whiskey Fire

One of the most destructive fires in the history of the city occurred on 18 June 1875, when a disastrous fire in the Liberties area of the city saw burning whiskey flow through the streets of the area like lava. A malt house and a bonded warehouse went up in flames, leaving the burning liquid to flow down Ardee Street and Mill Street. The fire began just after 8pm, and contemporary news reports give an idea of just how much burning booze was involved, with the Illustrated London News reporting:

The fire was at Reid’s malt-house and Malone’s bonded warehouse, in the Liberties. The former had above £2000 worth of malt in it, and the latter, which immediately adjoins it, had 1800 puncheons of whisky, the property of various distillers, and worth £54,000.

Read more about The 1875 Liberties Whiskey Fire


Explosion Severity: Propane Versus Natural Gas

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


Meet a NAFI member: Richard Meier

Meet a NAFI member: Richard Meier

Everyone at the National Association of Fire Investigators works hard to make sure our members reach their goals by supporting them with a variety of NFPA based trainings, certifications, and resources. When our members have the relevant education and resources that meet their needs, we’ve succeeded! We are proud of our team and are happy to share more about them with you.

Rich Meier is a Senior Staff Expert, Fire and Explosion Analyst, Lead Investigator with John A. Kennedy & Associates, Inc. He has a BS in Mechanical Engineering Technology from the University of Akron that he earned while working full time, serving in the US Army Reserves and being called to active duty.

Rich lived in Illinois, Ohio and Texas as a child, and ended up in Ohio.  He moved to Florida in 2000 because he had had enough of snow, and loves boating and diving.

How did you get started working in fire investigation?
I first met Pat Kennedy while dating his daughter Christine, now my wife.  When he found out I was both a mechanical engineer and an avid boater, he asked me to consult on a couple of marine cases, one explosion and one fire on an antique yacht.  From there I was hooked.  I studied fire investigation for about 2 years before joining Kennedy and Associates full time.  It is the most interesting thing I’ve ever done and now I can’t imagine doing anything else.

Why is NAFI an important organization for fire investigation?
I feel that NAFI puts a lot of emphasis on the basics.  We stress the scientific method because it’s a reliable roadmap to follow when you’re doing your investigation.  Yes, we also teach more complex topics, but we try to make sure you have the fundamentals in place first.  That includes all the requirements of NFPA 1033, in addition to other useful skills.

What is your favorite part of being involved with NAFI?
Meeting and networking with the members.  Through NAFI I know people on almost every continent.  I hear some interesting stories and learn a lot.  After teaching a class someone will come up and say “You know…” or “What about…?”  I’ll go find out and hopefully my class is that much better the next time I teach it.

What advice do you have for fire investigators just starting out?Learn everything you can and never stop asking questions.  Listen to other fire investigators when you’re at a fire scene, but don’t take anything as gospel.  Some really know what they’re doing and some don’t.  When you think you know everything, it’s time to look for another career.

What is a quote you live by?
I have a lot of favorites, so I’m not sure that I can narrow it down to just one.  Here’s two…

“Your present circumstances don’t determine where you can go; they merely determine where you start.” – Nido Qubein

“Do something every day that scares you.” – Eleanor Roosevelt


Jilin Baoyuanfeng poultry plant fire

On 3 June 2013, a fire at the Jilin Baoyuanfeng (吉林宝源丰) poultry processing plant in Mishazi (米沙子镇), a town about 35 km (22 mi) from Changchun, in Jilin province, People’s Republic of China, killed at least 120 people. More than 60 others were hospitalised with injuries.

Read more about Jilin Baoyuanfeng poultry plant fire.


Wrongful Arson Conviction: Case Review and Discussion

Robert J. Trenkle, CFI, CFEI

Presented at International Symposium on Fire Investigation, 2014

ABSTRACT
State of Michigan vs. Frederick Mardlin

On Monday, November 13, 2006 at 1410 hours (2:10 p.m.) a fire occurred at an owner occupied single family dwelling at 550 W. Mill Street, Capac, Michigan. The homeowner, Frederick Mardlin, lived there with his family and another family which was homeless and allowed to move in with the Mardlin’s. Prior to the fire, only Frederick Mardlin was home. He left the house to go to his brother’s house, who lived nearby. The fire was discovered by neighbors approximately 15-20 minutes after his departure. The fire was investigated by the local fire department, State Fire Marshal and a private investigator for the insurance company.

Numerous points made in the study by Paul Bieber, director, Arson Research Project, paralleled the Mardlin case, including mis-identifying the area of origin of the fire. Ignitable liquids were attributed to accelerating the fire although none were identified by laboratory analysis. Cognitive bias was apparent in their findings or they were the result of lacking knowledge in fire behavior, or both. Mr. Mardlin was convicted of Arson: Burning of a Dwelling House and Insurance Fraud. He was sentenced to ten years in prison. He served four years and was paroled. He was denied a new trial at the Appellate Court level and eventually the guilty verdict was vacated by the higher court. Hundreds of hours were spent by the appeals attorney, investigators and electrical engineer before the favorable outcome was reached. The discussion will explain the exhaustive efforts necessary to right the horrible wrong suffered by Mr. Mardlin.

Download the complete paper


Underground leaks in propane or natural gas lines

Neglected Gasline Sign

Looking for an underground leak in a propane or natural gas line?  Go back to nature.  In addition to using your nose to detect the smell of the odorant (usually a mercaptan or similar compound), it is not unusual to see flies buzzing around the point where gas is leaking out of the ground.  Odorants are similar to the chemicals given off by rotting food, and the flies can’t tell the difference.  Other signs are dead grass or vegetation.  If the ground is wet, you may also see bubbles.

(Sources: R.Meier; and Explosion Investigation and Analysis by P.Kennedy)