Fire investigation process

NFPA 92IM—Fire and Explosion Investigations." This section contains information to assist in improving the fire investigation process and the quality of information on fires resulting from the investigative process. Examples of the content of this section include ... 

The accident/near miss incident investigation form is the key document in the investigation process. This form could be used to investigate injury-producing accidents, high potential near misses, property damage events, fires, and environmental events. 

For example, most employees often feel embarrassed and distressed after being involved in an accident. What is even worse, supervisors may openly reprimand those involved in an accident in front of their peers. They may be suspended from their work duties for a period of time, reassigned to a completely different work area or task, or asked to attend refresher training classes. Some employees may even be fired after being involved in a workplace accident. As behavioral analysis indicates, such consequences discourage interest and participation in the accident investigation process. 

Schoen, W., U. Probst, and B. Droste. 1989. Experimental investigations of fire protection measures for LPG storage tanks. Proc. 6th Int. Symp. on Loss Prevention and Safety Promotion in the Process Ind. 51 1-17. 

At this point the location of the control panel(s) should be decided. Usually this should be a central location. This permits those watching the control panels to quickly investigate and determine the cause of any problems that might arise. As plants become more automated, it may be desirable to have two or more processes controlled from one location this could reduce the number of operators required. In this case the control room should be located in a relatively unexposed area near the edge of the processing area, but away from fired heaters.4 This is to protect both the employees and the equipment. 

Porous ultrafine tin oxide ethanol gas sensors92 in the form of a thin film have been prepared from tin alkoxide by the sol-gel process. The microstructural evolution of the tin oxide films, which affected the ethanol gas-sensing properties of the films, was investigated as a function of firing temperature and solution concentration. Theoretically, it was expected that ethanol gas sensitivity would increase monotonically with decreasing film thickness, but experimental results showed a maximum sensitivity at about 70 nm. The sudden decrease of the sensitivity below the thickness of 70 nm seemed to be due to the sudden decrease of film porosity, i.e., the sudden decrease of the number of the available sites for the oxidation reaction of ethanol molecules. Thus, it seemed that below the thickness of 70 nm, the sensitivity was governed by microstructure rather than by film thickness. 

The questions may be divided into specific areas of investigation usually related to consequences of interest, such as electrical safety, fire protection, or personnel safety. Each area is subsequently addressed by a team of one or more knowledgeable individuals. The team answers each question and addresses each concern (or indicates a need for more information) and identifies the hazard, potential consequences, engineered safety levels, and possible solutions. During the process, any new what-if questions that become apparent are added. Sometimes the proposed answers are developed by individuals outside the initial meeting, and then presented to the team for endorsement or modification. 

Figure 6-5 Maximum pressure for methane combustion in a 20-L sphere. The flammability limits are defined at 1 psig maximum pressure. Data from C. V. Mashuga and D. A. Crowl, Process Safety Progress (1998), 17(3) 176-183 and J. M. Kuchta, Investigation of Fire and Explosion Accidents in the Chemical, Mining, and Fuel-Related Industries A Manual, US Bureau of Mines Report 680 (Washington, DC US Bureau of Mines, 1985).

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