The Widespread Prevalence of Smoking - Report Example

Discussion on the Prevalence of Smoking Fires. Student Name Course Lecturer University Faculty Date The number of fires attributed to cigarettes has been on a sharp decline since the 1980s. Markowitz places the percentage of fires caused by conventional cigarettes at 2.8 in 2011 but points out that cigarette fires are considered the deadliest fires second only to arson fires (Markowitz, 2). The number of forest fires attributed to smoking is now about 10 percent of where they stood in 1980 (Butry, Prestemon and Thomas 2014, 790). This essay examines the reasons for the drop in cigarette attributed fires and examines why the estimates have been so much higher in past years. Cigarettes and Combustion Cigarettes burns by smoldering combustion which occurs where the fuel, heat and oxygen occur in insufficient proportions to cause a flame but enough to cause decomposition of the fuel. Cigarettes in particular combust by way of diffusion burning meaning that the oxygen and the fuel are not already mixed at the onset. The smoldering capacity of cigarettes rests on two factors; firstly, the tobacco particles in a cigarette allow for easy circulation of oxygen, and secondly, the tobacco particles provide a large fuel surface area. Smoldering fires have low temperatures and will not convert into a flame unless the proportions of the three elements are changed. In the case of a cigarette, altering the elements could involve placing it next to a flammable material. Cigarettes burns in two phases. During the Solid-phase the combustion of the tobacco are 790 centigrade during smouldering and 900 centigrade when puffed. When measured from the outside the temperatures are at 675 centigrade during smoldering and 930 centigrade when puffed. At the gas phase stage, temperatures are at 790 centigrade during smoldering and 860 centigrade when puffed (Liu and Woodcock 2014, 258). Experiments to measure the temperature of burning cigarettes measured by infrared equipment recorded that temperatures fluctuated heavily within a 2 second window of the puff and achieved temperatures of up 1200 centigrade. Liu and Woodcock describe that 2 second period as comprising three stages. First the increased oxygen flow caused an increase in temperature; secondly the cigarette hits peak temperatures and finally a decrease in temperatures reflecting the decrease in the rate of oxygen flow (Liu and Woodcock 2014, 260). This infrared method also allowed researchers to observe that there were distinct burning events during the second stage linked to the combustion of tobacco subjected to the highest oxygen flow around the perimeter of the cigarette (Liu and Woodcock 2014, 264). A smoldering cigarette can cause another material to smolder or it can provide the conditions that lead to a flame. Transition from smoldering to flaming is influenced by oxygen flow which is enhanced if a window is open nearby. If conditions are met, it tends to occur between 20 minutes and a few hours of the smouldering. Grass material has been observed to burst in to flame when the speed surpasses 0.83m/s point. Once the transition occurs, the flame is identical to one started by other means. Ignition of a solid such as a mattress by a smoldering cigarette causes pyrolysis that creates char. It is this char, which contains more carbon than the original mattress that then undergoes the exothermic process of smoldering. A smouldering item will combust slower than a flaming one, for instance a smoldering chair smolders at 0.1g/s and a flaming one at 100 g/s (Babrauskas and Krasny 1985, 5). One 1985 study noted that cigarettes had a lower likelihood of igniting flat surfaces like mattresses than furniture with vertical surfaces or crevices and that the cigarette would likely have to be covered by bedding to ignite (Babrauskas and Krasny 1985, 3). The actual transfer of smoldering to the furniture is aided by the presence cellulosic material which then transfers the heat to the padding material. The smoldering can be transferred by either oxidative or pyrolytic pathways. Flawed Investigations and Wrongful Convictions One case that illustrates the impact of applying bad science in fire investigations is the State of Texas v. Ernest Ray Willis, in which Willis was convicted of arson that caused the death of two people in 1987 but was exonerated of all charges17 years later. His conviction had been based on a series of erroneous assumptions made by the fire investigator. For instance he had claimed that it was impossible that a cigarette could have ignited Willis furniture causing smoldering that transitioned into a flaming fire. He disputed the possibility that the flame would behave like any average fire and he also claimed that the fire pattern on the floor was evidence of accelerant. Some of the erroneous assertions made by the investigators were actually in being propagated by government institutions. Lentini points out that both the Law Enforcement Assistance Administration (LEAA) and the National Bureau of Standards (NBS) had published a number of these myths in organisational handbooks during the late seventies and early eighties that came to be viewed as authoritative. Lettini also points out that as at 2006, government publications were still carrying theories contradictory to one another. For instance, the Army’s Field Manual, Law Enforcement Investigations was still claiming that crazed glass indicated rapid heating even though the NFPA had shifted from that theory (2006, 12). Some of the widely propagated myths included claims that charred wood with textured surface was proof of extremely high heat, or that the depth of the char could indicate the origin of the fire, or that the certain types of cracks in glass proved high heat and therefore that an accelerant was present. In reality, the products of combustion can provide clues on the origin and spread of a fire but care should be taken to keep hypotheses within the remit of what is proven by laboratory testing. The pace of a fire that has been ignited by a smoldering cigarette is no different from a fire ignited in other ways despite past assumptions have held that these types of fires burn slow. Improving Fire Investigations. Fire forensics has long relied on disproven science and poor investigative practices to establish the cause of fires. Many of these assumptions were actually given legitimacy by the Bureau of Standards, when they were reproduced in their Fire Handbooks. There were for instance, erroneous assumptions about the level heat produced by different materials. It was also wrongly believed that flashover fires originated where the burn was lowest and where the char is deepest (Lettini 2012, 5). The need for constant laboratory retesting is made apparent by the discovery that some of the fabrics that had been classified as “worst case” fabrics did not actually ignite and that what had been observed in initial tests was actually the igniting of the foam underneath the fabric (Babrauskas and Krasny 1985, 6). The Guide for Fire and Explosion Investigations (NFPA 921), was drafted to address these issues. It provides acknowledged scientific method of determining how a fire started. Alongside The Standard for Professional Qualifications for Fire Investigator (NFPA 1033), it also sets out the process that a fire investigator must follow. It requires them to first collect data and then apply inductive reasoning to analyze it and develop a hypothesis that answers the when, how and where questions. This hypothesis is then tested by deductive reasoning by comparing it against the established science and recreating conditions of the specific fire in the laboratory. The NFPA requires that hypotheses that fail the deductive reasoning stage be discarded. It also cautions against cognitive biases such as expectation bias, which is the tendency to under play evidence that conflicts with the fire investigators investigations, and confirmation bias which is where evidence is collected and analyzed to confirm the hypothesis rather than challenge it. Hypothesis are drawn against two levels of certainty; probable and possible. The NFPA requires the investigator to rank his hypothesis along this scale. A fire investigator can no longer allege arson because he is unable to find the ignition source as occurred in the Willis case. Applying algebra formulas, scientists can create mathematical models that predict the life of a flame by taking into account all the variables. There are many models available but Fire Dynamics Simulator (FDS) is the model most in use by the National Institute of Standards and Technology (NIST). These mathematical models are primarily used to design fire protective measures but have been applied to test investigators hypotheses. Their main shortcoming is that they rely on accurate input of all the factors relevant and it is for this reason that their predictions must therefore be independently confirmed and not taken as standalone evidence. The NFPA also introduces review procedures including the administrative review conducted internally by the agency to determine compliance to agency procedures. Technical reviews which are conducted by experts on the actual investigations and peer reviews which are mostly applied to published documents. One of the results of establishing the science and the procedures expected of fire investigators is that it is less likely that a fire will be wrongly attributed to smoking. Measures to Prevent Smoking Fires The National Fire Protection Association (NFPA) ascribes the gradual reduction in cigarette related fires to a number of factors. Among them is the 25% decline in the number of US smokers since 2000 as measured in 2011. Secondly, household items like upholstery and mattresses are now required to be more fire resistant leading to a 93% decline in cigarette fires related to these items, between 1980 and 2011. Thirdly, the complete elimination of non- RIP cigarettes from the market (Hall 2007, 3). The Center for Disease Control 2014 estimates, place smoking prevalence in the US at 16.8% adults while an estimated 3.7% of adults used e-cigarettes. The trends over the last few years have seen declines in conventional smoking and increases in e-cigarette vaping (Schoenborn and Gindi 2015, 8). E-cigarettes require no combustion as they operate on batteries. While there have been recorded instances of batteries malfunctioning and causing fires, e-cigarettes generally pose low fire risk (Farsalinos and Polosa 2014, 68). Over the years, two approaches were adopted to address cigarette related fires. Firstly, making cigarettes less likely to ignite a material and secondly, making materials around the home less flammable. With regard to the first approach, all fifty US states have now passed “fire safe cigarette laws”. This is legislation that now requires that all cigarettes sold in the US have Reduced Ignition Propensity or RIP properties. An RIP cigarette is one that is designed to extinguish when it is not being puffed. These cigarettes therefore have a lower capacity to ignite fires. Compliance of manufacturers to the fire safe laws is measured against the Standard Test Method for Measuring the Ignition Strength of Cigarettes or ASTM E2187. Cigarette manufacturers achieve RIP compliance by using wrapping paper that is less permeable to oxygen as well as specially banded with chemical (Wilhelm 2008, 1). The ignitability of mattresses is monitored against the compulsory the Standard for the Flammability of Mattresses and Mattress Pads as provided in the Code of Federal Regulation (CFC) part 1632. The standard applied for household upholstery is "Upholstered Furniture Action Council (UFAC) standard," and is voluntary. The establishing the ignitability of fabric and foam was conducted by placing a non RIP cigarette smoldering at the rate of O.lOtO.01 mm/s on furniture and covering with fabric. The length o f the char was used to determine the fabrics ignitability and was applied in the development of UFAC specifications on fabrics and polyurethane foam (Babrauskas and Krasny 1985, 6). The expected impact of fire safe cigarettes may have initially been over ambitious as results of one study suggest that the use of RIP cigarettes alone do not have great impact on reducing fire risks. In the experiments conducted, RIP brands were placed on or near mattresses with varied results. The experiments further found that the duration of how long a cigarette burned before self extinguishing was irrelevant on whether and how smoldering of the mattress material would begin (Mehta 2012, 4). That said one study conducted prior to the mainstreaming of RIP cigarettes found that cigarette characteristics that cigarette qualities such as the porosity, filter and filter length contributed to the potential of cigarette fires (Karter 1994, 402). This is instructive when one considers that even today the type of wrapping paper and filter used differs from brand to brand with some more porous than others. So even with RIP mainstreamed, some cigarette brands carry greater fire risk than others. In summation, it is likely that many of the fires that were in the past blamed on cigarettes actually had other causes. The growing emphasis on empirical evidence and the introduction of investigatory standards and procedures has helped reduce the tendency to just select the easiest explanation for a fire. This is likely to be the main reason that fewer fires are being blamed on cigarettes. Other possible reasons is that the drop in cigarette smoking and the uptake of the e-cigarette, provides a more fire safe way to consume cigarettes. The introduction of RIP cigarettes may also be playing a role, although it is not as significant as once anticipated. References Babrauskas, V. & Krasny, J., 1985. Fire Behavior of Upholstered Furniture, Gaithersburg, MD: U.S. Government Printing office. Butry, D.T., Prestemon, J.P. & Thomas, D.S., 2014. Investigation of the decline in reported smoking-caused wildfires in the USA from 2000 to 2011. International Journal of Wildland Fire, 23(6), 790–798. Farsalinos, K.E. & Polosa, R., 2014. Safety Evaluation and Risk Assessment of Electronic Cigarettes as Tobacco Cigarette Substitutes: A systematic review. Therapeutic Advances in Drug Safety, 5(2), 67–86. Hall, J.R., 2007. The Smoking-Material Fire Problem, Quincy, MA: National Fire Protection Association. Karter, M.J. et al., 1994. Cigarette characteristics, smoker characteristics, and the relationship to cigarette fires. Fire Technology, 30(4), 400–431.  Lentini, J.J., 2006. Scientific Protocols for Fire Investigation, Boca Raton, FL: CRC Press Lentini, J.J., 2012. The Evolution of Fire Investigation, 1977-2011. ABA Magazine, Criminal Justice, 27(1), 1–21. Liu, C. & Woodcock, D., 2014. Observing the Peripheral Burning of Cigarettes by an Infrared Technique.Contributions to Tobacco Research, 20(4), 257–264. Liu, C., The ASTM2187-02b Standard Method on Testing Cigarette’s Ignition Propensity. British American Tobacco, 2187(02). Markowitz, S., 2010. Where There's Smoking, There's Fire: The effects of smoking policies on the incidence of fires in the United States. NBER Working Paper Series, 16625, 1–39. Mehta, S., 2012. The burning character Cigarette Ignition Risk Project, Bethesda, MD: Division of Combustion and Fire Sciences Directorate for Engineering Sciences U.S. Consumer Product Safety Commission. Schoenborn, C.A. & Gindi, R.M., 2015. Electronic Cigarette Use Among Adults: United States, 2014. NCHS Data Brief; Centres for Disease Control and Prevention, 217, 7–20. Wilhelm, R., 2008. Where There's Smoke There Doesn't Have to Be Fire. ASTM 2187. Available from: http://www.astm.org/toolkit/images/astm information/case_studies/case_study_where_theres_smoke.pdf [Accessed February 18, 2016]. Read More