Fire Investigation

A scale from 0 to 6 has been developed to allocate a DEAD, where 0 shows no visible damage and 6 indicates full consumption. Thirty-nine “newcomers” evaluators performed an analysis of damage to the wall surface, completing 66 classifications first without the DOFD method, and second, repeated qualification using the new DOFD method. The results indicated that novice evaluators were more reliable in their analysis of the DEAD to the drywall using the DOFD method. These results support the use of standardized processes to reduce variability in the collection and interpretation of data.

An optical measurement method has been developed to arrive at the optical properties of smoke deposited from a smoke layer on glass filters. Based on this work, the researchers used gravimetric measurements of these filters to demonstrate and validate an analytical model for thermophorean-based smoke deposition. That is why a new optical measurement method has been developed for use with digital photography and digital image analysis. The researchers used the ImageJ software and a Kodak gray scale and found a lot between optical measurement methods and images of smoke patterns developed along the surfaces of the walls. Their investigation showed that “the smoke pattern was determined for wall tests and showed a difference between the test conditions and a very good match for the method for all test conditions” . They also stated that “depending on the area of the clean room, the height of the flame and the size of the fire can be calculated” .

Shanley et al. ) states that the available “fresh” air source from adjacent rooms will have a significant impact on whether or not the cartridges generated by ventilation prevail to such a size. The literature search into the use of fire patterns in the profession of fire investigation illustrates various gaps in the overall process of using damage to determine an area of origin. First, a poor assumption by many of the fire research, textbook and research guides was that any researcher can evenly evaluate the distribution Fire Expert Investigator California of DOFD (Shanley et al. 1997; NFPA 2014; Gorbett et al. 2010). However, this has not been demonstrated by aptitude test conducted to determine the area of origin based on visible observations (Carman 2008; Tinsley and Gorbett 2013). Several recent studies have yielded processes to help identify different degrees of damage, including a degree of fire damage to visible damage (Gorbett et al. 2013), a standardized depth measurement system (Mealy et al. 2013), and the use of digital image analysis (Riahi et al. 2013).

In the absence of reliable eyewitness statements or registration of arson, the investigator must determine the origin by expert observation and interpretation of the physical evidence (p. E.g. fire patterns) in an attempt to reconstruct the development of fire. As such, determining the origin of fire is largely a matter of recognition and interpretation of the fire pattern . Fire and arson investigators are sworn law enforcement officers and work for law enforcement agencies, police forces or fire brigades. They are specially trained to identify and collect evidence related to fires and to determine their causes.

Many calculations focus on simplifying geometric shapes, such as cylinders, cones, surfaces and point targets. Only one article related to the use of visible carbon appearance was identified in the variable DOFD identification where quantitative measurements were attempted . This article repeated the same misconception about crocodiles announced at the time, but despite this connection, the aim of the article was to establish a method to define different DOFDs for visible observation of char . In this work, the authors described a system that described character in a range from “Number 0 Char” to “Number 10 Char”, with the number 10 char as the highest damage level. The level of damage was varied depending on the visible appearance of the number of cracks within the specified distances and the widths of those cracks.

Damage data used by fire investigators in determining origin begins with the investigator’s ability to observe variable damage along content surfaces, walls, ceiling, floor and structural limbs. Variable DOFD identification throughout the compartment serves as the basis for interpretation by the researcher. Textbooks, guides and fire research studies describe the use of demarcation lines or areas to assess damage. The damage areas and boundaries of those areas are often known as areas and demarcation lines. Marking areas are locations along a surface with similar damage characteristics (p. E.g. extent of damage, type of fire effect, color, texture) and are very close together. The demarcation lines are “the limits that define the differences in certain heat and smoke effects of fire on different materials.

The purpose of this literature search is to identify the work done specifically for forensic applications that have been performed to identify ways to observe and characterize different degrees of fire damage by means of measurable or visible means. The wood and plasterboard were the only materials that had enough literature in this context to assess. He noted that the effect of ventilation was the least understood factor and that the large-scale patterns generated by ventilation were identified, sometimes larger than those of the cartridges caused by the plume or origin. Their study noted that clean burns were observed on the surfaces of the walls under the windows opened during the fire and that the damage extended from the windowsill to the floor.


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