Did Nero play the fiddle while Rome burned?

AD 64, Jul 18th:  Nero’s Rome burns

The great fire of Rome breaks out and destroys much of the city on this day in the year 64.  Despite the well-known stories, there is no evidence that the Roman emperor, Nero, either started the fire or played the fiddle while it burned.  Still, he did use the disaster to further his political agenda.

The fire began in the slums of a district south of the legendary Palatine Hill.  The area’s homes burned very quickly and the fire spread north, fueled by high winds.  During the chaos of the fire, there were reports of heavy looting.  The fire ended up raging out of control for nearly three days.  Three of Rome’s 14 districts were completely wiped out; only four were untouched by the tremendous conflagration.  Hundreds of people died in the fire and many thousands were left homeless.

Although popular legend holds that Emperor Nero fiddled while the city burned, this account is wrong on several accounts.  First, the fiddle did not even exist at the time. Instead, Nero was well known for his talent on the lyre; he often composed his own music.  More importantly, Nero was actually 35 miles away in Antium when the fire broke out.  In fact, he let his palace be used as a shelter.

Legend has long blamed Nero for a couple of reasons.  Nero did not like the aesthetics of the city and used the devastation of the fire in order to change much of it and institute new building codes throughout the city.  Nero also used the fire to clamp down on the growing influence of Christians in Rome.  He arrested, tortured and executed hundreds of Christians on the pretext that they had something to do with the fire.

Source: History.com 

Ignition Propensity of Cannabis Cigarettes

Zachary J. Jason, PE, CFEI
Dennis E. Shelp, MS, PE, CFI, CFEI
John L. Schumacher, MChE, PE, CFI, CFPS
Todd J. Hedglin, CFI, CFEI
AEI Corporation
Littleton, CO, USA

Presented at International Symposium on Fire Investigation, 2014


It is well known that cigarettes are the leading cause of fire deaths in the United States.  The National Fire Protection Association (NFPA) reports that in 2011 alone, there were over 90,000 smoking-related fires, contributing to over 540 civilian deaths, 1,640 civilian injuries, and $621 million in direct property damage. However, the NFPA statistics, collected from The National Fire Incident Reporting System (NFIRS) and the NFPA annual survey, define “Smoking Materials” as lighted tobacco products (typically tobacco cigarettes). There is little to no data regarding fires caused by cannabis, or what will hereafter be referred to as marijuana cigarettes.

With the recent legalization of marijuana in the states of Colorado and Washington, pending potential legalization in 13 other states, and 20 states with medical-marijuana systems already in place the availability and usage of marijuana is becoming more commonplace. This raises many interesting questions with regard to fire safety as it relates to marijuana cigarettes. For example, what are the burn times and smoldering capability for marijuana cigarettes? How do marijuana cigarettes compare with tobacco cigarettes in their ability to initiate smoldering combustion in upholstered furniture and mattresses? To date, research regarding these questions has been difficult due to the illegal status of cannabis, and currently very little is known about the ignition propensity and combustion characteristics of marijuana cigarettes. Given the recent changes in Colorado law, however, AEI Corporation has performed some of the first scientific testing of its kind looking at the smoldering and burning behavior of marijuana cigarettes.

This paper outlines the first phase of our research into the overall fire hazards of marijuana cigarettes and compares the ignition characteristics of marijuana to those of tobacco, when tested in accordance with current test methods adopted for the tobacco industry. More specifically, our testing quantifies the ignition strength of marijuana cigarettes and their propensity to ignite soft furnishings based on the parameters set forth in American Society of Testing and Materials (ASTM) Standard E2187-2009, Standard Test Method for Measuring the Ignition Strength of Cigarettes.  The results of our tests evaluating ignition propensity of marijuana cigarettes are presented in comparison to those of tobacco cigarettes tested under the same conditions. In addition, the effects of different variables on the burning, smoldering, and ignition propensity of marijuana cigarettes will be examined.

Download the complete paper

Chicago Fire of 1874

The Chicago Fire of 1874 was a conflagration in Chicago, Illinois, that took place on July 14, 1874. Reports of the extent of the damage vary somewhat, but sources generally agree that the fire burned forty-seven acres just south of the Loop, destroyed 812 structures and killed 20 people. The affected neighborhood had been home to Chicago’s community of Jewish immigrants from Russia and Poland, as well as to a significant population of middle-class African-American families; both ethnic groups were displaced in the aftermath of the fire to other neighborhoods on the city’s West and South Sides.

The fire insurance industry’s National Board of Underwriters responded to the fire by demanding widespread changes in Chicago’s fire prevention and firefighting efforts, and ultimately encouraged fire insurers to cancel all coverage of buildings in the city in October. Many insurers did halt their activities in Chicago, and only returned to issuing policies in the city after the municipal government adopted many of the suggested reforms.

Source: Wikipedia

Metallurgy and Fire Investigation

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

Presented at International Symposium on Fire Investigation, 2012


NFPA 921 Guide for Fire and Explosion Investigations recognizes the need for specialists for certain aspects of fire cause investigations. One such area is metallurgical failure analysis. Examples of metallurgical aspects that overlap the fire investigation field include vessel and pipeline failures from corrosion or welded joint failures causing loss of containment (i.e., natural gas); wear and mechanical breaks or failures that generate sparks or frictional heating that cause ignition; and elucidation of heat or fire versus electrical arc damage to current carrying components, such as conductors, motor windings, contacts, and fuses. Equally important, metallurgy can be used to determine the effects of fire on low-melting temperature alloys, such as brass and brazed joints, to determine when damage occurred and if it contributed to the cause of a fire or was a result of fire exposure. Like fire investigation, metallurgical root-cause failure analyses are performed according to a recognized professional standard methodology that meets the criteria for admissibility. Here, key elements of a metallurgical-based failure analysis are highlighted with specific metallurgical-based fire cause investigation case studies.

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Fitting a Square Peg into a Round Hole

Fitting a Square Peg Into a Round Hole – Fire Classification Under NFPA 921

Brian P. Henry and Andrew L. Smith

This article will be presented at ISFI 2016

This article will explore an important, but largely ignored, topic in NFPA 921 – should fire investigator experts classify fires? Does a classification of a fire as incendiary serve a purpose? Why did the NFPA implement authoritative guidelines permitting fire investigators the ability to separate fires into one of four distinctly defined categories? These important questions will be explored in detail below.

To begin, we must first ask ourselves why we investigate fires. As a society, we investigate a fire to find the root cause to prevent the fire from happening again. Public welfare and safety are huge concerns. Fire investigation implicates potential criminal responsibility. Some say the purpose of fire and explosion investigations is much broader than just determining the cause of a fire or explosion incident. The goal of any particular fire investigation is to come to a correct conclusion about the features of a particular fire or explosion incident that resulted in death, injury, damage, or other unwanted outcome.

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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

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.

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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

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.

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Which toy was one of the fastest and most complete recalls in the history of CPSC?

The recall of all Hoverboards (a self-balancing 2 wheeled cross between a skateboard and a Segway) may be the fastest and most complete recall in the history of the CPSC (Consumer Product Safety Commission).  In addition to the numerous fires attributed to the lithium-ion battery powered device, there have been numerous injuries due to users falling off their hover boards. (Source: CNN, CPSC, TheVerge.com )

Are you a fire investigation expert?

Abstract deadline extended for 2016 International Symposium on Fire Investigation Science and Technology.

Deadline extended!

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