• Single electrical short resulted in death of four, highlighting risks from smoke hazards
• Academics note increased use of A/Cs require better smoke/fire safety systems 

BY Ruwan Laknath Jayakody Even though deaths due to smoke inhalation are rare, owing to increased air conditioning and insulation of houses, smoke-related hazards have increased, and therefore, the installation of smoke alarms and fire sprinkler systems are recommended, considering the case of a family that was found deceased inside a locked house due to this very issue. This recommendation was made in a case report on a “Tragic death of a family due to a house fire” which was authored by P.S.M.D. Senarath, C.S.A. Nandasiri, and M. Vidanapathirana (all attached to the University of Sri Jayewardenepura Medical Sciences Faculty’s Forensic Medicine Department) and published in the Medico-Legal Journal of Sri Lanka 6 (2) in December 2018. In addition to thermal hazards, housing-related trends such as the lack of space, insulation, and poor ventilation, have, Senarath et al. noted, further increased fire-related hazards. It is also observed that house fires which cause both injury and death are not common in Sri Lanka. Hence, Senarath et al. presented a related case that highlights the nexus between the hazards of fire and the advancements in our lifestyles. Case report A 65-year-old businessman, his 53-year-old wife, 13-year-old daughter, and 13-year-old niece who came to visit them were found dead inside their air conditioned, airtight, and locked house on a morning, by the driver who came for duty at the house. When the front door was broken open by the Police, the floor, ceiling, furniture, and rest of the interior of the house were found to be blackened with soot. The man’s body was found slumped on a chair in the living room, near the front door. The wife’s body was found lying on the floor of the master bedroom. The bodies of the two children were found lying on the floor of the living room at two different places. There were sooty footprints on the floor and black fingerprints on the wall near the front door. The pantry area which freely opened into the living room had evidence of fire. There was a burnt mobile phone charger, which was connected to a plug point with an intact phone, with a maximum burnt area surrounding it, thus making it the suspected origin of the fire. Wooden pantry cupboards were partially burnt and most plastic equipment in that area was found to have melted. The escape points such as doors and windows were not nailed from outside. At the autopsy, all four bodies were found to be covered with black soot, with no burns in the bodies or clothing. They were clad in night clothes. All bodies displayed hypostasis (the accumulation of fluid or blood in the lower parts of the body or organs under the influence of gravity, which occurs in cases of poor circulation or after death) on the dependent areas. Soot mixed with mucus was found in the nostrils, mouth, upper airways, and lower airways, spreading beyond the secondary bronchioles (air passages inside the lungs that branch off like tree limbs from the bronchi – the two main air passages into which air flows from the trachea/windpipe after being inhaled through the nose or mouth). On musculo-skeletal dissections, no injuries suggestive of intentional violence were identified in any of the bodies. Blood samples that were sent to the Government Analyst’s (GA) Department were positive for carbon monoxide (CO) and cyanide (CN) and were free of other toxins. The histopathology (diagnosis and study of diseases of the tissues) of the lungs showed soot beyond the secondary bronchioles, pulmonary (lungs) congestion, and pulmonary haemorrhages (bleeding). The electrical expert confirmed the point of origin of the fire as the mobile phone charger. The cause of death was given as death due to smoke inhalation. The circumstance of the deaths was ascertained to be accidental. Senarath et al. explained that the majority of accidental fire-related deaths take place within buildings, starting by ignition and as a small fire, which then spreads to produce more heat and smoke. At the early stages of the fire, Senarath et al. pointed out, it is fuel controlled and usually not affected by the enclosure; however, it then grows at a slow or fast rate, depending on the fuel type, and the ventilation available. Smouldering and flameless fires have, according to A.A. Alarifi, H.N. Phylaktou, and G.E. Andrew’s “What kills people in a fire? Heat or smoke?”, a slow and lengthy growth period and may extinguish spontaneously without reaching a fully developed state. As Y. Alarie noted in “Toxicity of fire smoke”, the progression, magnitude, and toxic threats of fires will differ depending on whether the person is in the room of origin or away from the room of origin, whether the person is awake or asleep, and whether the person, owing to age-related factors (infants and the elderly) or other factors (being in an intoxicated state), is capable or incapable of escaping. If the person is in the room of origin of the fire, the immediate effects, according to Senarath et al., would be a large number of organic and inorganic chemicals in the smoke causing sensory irritation of the eyes with increased lacrimation (flow of tears) resulting in impaired vision, coughing or choking, following bronchial (the larger air passages of the lungs, including those that lead from the trachea/windpipe to the lungs and those within the lungs) irritation, heat induced effects and high smoke density, all causing further limitation of vision. Although there is some disorientation per Alarie, the normal individual’s natural reaction would be an attempt made to escape the situation. In the instant case, the victims were in their night clothes and were found dead at three random places with foot and palm print evidence of volitional activities. There were indications of some volitional activity in all four victims before the death, in the form of walking and touching the walls with hands with soot, which Senarath et al. added, indicate that they had attempted to escape, probably in a semi-conscious state, but had failed. It is reiterated that there was no evidence of intentional attempts of preventing their escape such as incapacitation with injuries or poisoning or the blocking of escape routes such as by nailing the door or windows from outside. The spreading of smoke, Senarath et al. further explained, will form a hot layer at the ceiling level first, later spreading down towards the floor. This will, as Alarie elaborated, reduce the level of oxygen (O2), and when the level of O2 becomes less than 7%, it is a major cause of incapacitation and death. Smoke will contain CO which is, as R.A. Anderson, A.A. Watson, and W.A. Harland noted in “Fire deaths in the Glasgow area: Role of CO”, a dangerous and potentially lethal gas. Usually, very high CO concentrations are needed in order to cause carboxyhaemoglobin (COHb – the complex that is formed within red blood cells when hemoglobin [an iron rich protein found in red blood cells that is primarily responsible for carrying O2 from the lungs to the rest of the cells in the tissues and organs] is exposed to CO), of about 50-60% in the blood. If the burning material contains nitrogen (N2), hydrogen cyanide (HCN) will be emitted, which, A.C.P. Antonio, P.S. Castro, and L.O. Freire’s “Smoke inhalation during enclosed space fires: An update” and R.A. Anderson and W.A. Harland’s “Fire deaths in the Glasgow area: The role of HCN” emphasised, is much more dangerous than CO, due to its greater potency to be absorbed when inhaled and its quick action on tissues. If the burning material contains chlorine (Cl), bromine (Br), or if fluorine (F – for example, in polyvinyl chloride [PVC] burning), hydrogen chloride (HCl), phosgene (COCl2), hydrogen bromide (HBr), or hydrogen fluoride (HF) would be emitted, as per Senarath et al., it would exacerbate the irritation and choking effects of the smoke, with such, according to K. Detwiler-Okabayashi and M. Schaper’s “Evaluation of the respiratory effects of thermal decomposition products following single and repeated exposures of guinea pigs”, causing delayed, long lasting pulmonary effects in survivors. In the present case, even though CO and CN were found in the blood, their quantitative assessments were not performed. Discussing the findings further, Senarath et al. maintained that if the person is placed away from the origin of the fire, heat and O2 depletion would not be significant factors causing the deaths, and that, per Alarie, incapacitation and death would be due to the combined effects of CO, HCN, and other toxic gases. In the current case, no burn injuries were detected in any of the victims, and according to Senarath et al., the hypostasis and positive CN and CO in the blood indicated that the deaths were due to toxic gas inhalation, while the absence of heat effects on any of the bodies indicated that they were considerably away from the origin point of the fire. The presence of soot-mixed mucus in the windpipe and beyond the secondary bronchioles indicated, Senarath et al. explained, that they were alive at the time of the onset of the fire, a fact which could have been further supported had the GA performed the quantitative analysis of CO and if its concentration had exceeded 10%. In conclusion, Senarath et al. noted that a known hazard of sleeping in fully airtight houses is, especially with the inadvertent plugging of instruments like mobile phones, the latter can get heated, and in turn, become a source of a fire. As this is a major health hazard, the American Academy of Paediatrics have recommended in “Reducing the number of deaths and injuries from residential fires”, the installation of household smoke alarms and fire sprinkler systems and to have an escape plan with at least two exit points, in particular when the rooms are airtight.