Fire Hazard Identification

Identifying and analyzing fire hazards and scenarios is the next step in a fire risk assessment. The hazard identification should be structured, systematic, audit-able, and address all fire hazards, including nonprocess fires. The result of the hazard identification is a list of potential fire hazards that may occur at the facility, for example, jet, pool, flash, BLEVE, electrical, or Class A fires. This list should also include the location where each fire could occur. Hazard identification techniques used to identify potential hazards are shown in Table 6-1. 

Each identified hazard will have a range of possible scenarios it may not be reasonable to evaluate every scenario. Therefore, representative fire scenarios should be chosen to cover a range of foreseeable scenarios. The scenarios to evaluate are those where the initial release and ignition characteristics are likely to cause the most extensive damage, loss of production, and the greatest risk to personnel. The fire scenarios selected should have a sufficient inventory that will burn long enough to cause failure of equipment and/or the structure. 

Hazard and Operability Studies (HAZOP) Other methods 

Smaller fire scenarios that can escalate and less severe but very likely scenarios should also be considered. 

Fire hazard analysis (FHA) is the process to determine the size, severity, and duration of a scenario and its impact on personnel, equipment, operations, and the environment. Chapter 5 provided details of performing an FHA. The following paragraphs provide an overview of the FHA process. For example, one scenario could be a seal failure where the material being released is ignited and afire results. In assessing consequences, several questions must be considered  

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The health rating is provided on the left at the 9 o clock position and is colored blue. The flammability rating is provided at the top or 12 o clock position and is colored red. The reactivity hazard is provided on the right at the 3 o clock position and is colored yellow. The relative rankings for each hazard are indicated in each quadrant. Special hazard identifiers are provided in the bottom quadrant at the 6 o clock position, which is usually white. Special hazard qualifiers generally include radioactivity, explosives, corrosive, water reactive, oxidizer, etc. The NFPA fire hazard identification scheme is somewhat limited as it only identifies relative potential hazards with the individual material. It does not identify the material itself or all of its potential reactions with other materials. See Figure C.3 for a depiction of this placard. See also Chemical Hazard Label Hazardous Materials Identification System (HMIS ) NFPA 704, Standard System for the Identification of the Hazards of Materials for Emergency Response. 

Fire hazard identification and extinguisher use Principles and conditions of combustion... 

Fire and Explosion Index (Ffrom fires and explosions. frequency The rate at which observed or predicted events occur. HAZOP HAZOP stands for hazard and operabihty studies. This is a set of formal hazard identification and ehmination procedures designed to identify hazards to people, process plants, and the environment. See subsequent sections for a more complete description. 

SOURCE Reprinted with permission from NFPA 704, Standard System for the Identification of the Fire Hazards of Matenals, National Fire Protection Association, Quincy, Mass., 1990. This printed material is not the complete and official position of the National Fire Protection Association on the referenced subject, which is represented only by the standard in its entirety. 

NFPA 704 Standard for the Identification of the Fire Hazards of Materials for Emergency Response. National Fire Protection Association, Quincy, MA. 

In this study detailed fault trees with probability and failure rate calculations were generated for the events (1) Fatality due to Explosion, Fire, Toxic Release or Asphyxiation at the Process Development Unit (PDU) Coal Gasification Process and (2) Loss of Availability of the PDU. The fault trees for the PDU were synthesized by Design Sciences, Inc., and then subjected to multiple reviews by Combustion Engineering. The steps involved in hazard identification and evaluation, fault tree generation, probability assessment, and design alteration are presented in the main body of this report. The fault trees, cut sets, failure rate data and unavailability calculations are included as attachments to this report. Although both safety and reliability trees have been constructed for the PDU, the verification and analysis of these trees were not completed as a result of the curtailment of the demonstration plant project. Certain items not completed for the PDU risk and reliability assessment are listed. 

Also indices such as the Dow Fire and Explosion Hazard Index and the Mond Index have been suggested to measure the degree of inherent SHE of a process. Rushton et al. (1994) pointed out that these indices can be used for the assessment of existing plants or at the detailed design stages. They require detailed plant specifications such as the plot plan, equipment sizes, material inventories and flows. Checklists, interaction matrices, Hazop and other hazard identification tools are also usable for the evaluation, because all hazards must be identified and their potential consequences must be understood. E.g. Hazop can be used in different stages of process design but in restricted mode. A complete Hazop-study requires final process plans with flow sheets and PIDs. 

Hazard Identification Health 3 Can cause serious temporary or residual injury. Fire fighters should be wearing fully protective clothing including self contained breathing apparatus. 

M, Recommended System for Identification of Fire Hazards of Materials,... 

Cleaning materials and their methods of use can present significant and, frequently, undetected fire hazards. Any cleaning chemical or material brought into a facility should be reviewed for potential hazards using Material Safety Data Sheet (MSDS) information as a part of the material s hazard identification element of the overall fire prevention program. Cleaning activities should not be allowed to add unreasonable hazards to a facility. 

A program is necessary for identifying all materials in the workplace, and making employees aware of the hazards of these materials and the necessary precautions to be taken to prevent or control personnel exposure. Materials Hazard Identification and information gathering is an essential element of fire prevention. The hazardous properties of all chemical substances used in the workplace should be known in order to develop the appropriate design, routine handling practices, and fire prevention plan. 

Flammability properties of materials are clearly important for fire prevention but there are other properties that are also significant. There have been a number of severe fire incidents initiated by a material s reactivity properties that were previously unrecognized or unknown to the user. The development of a Materials Hazard Identification program requires knowledge of a material s toxicity and reactivity, as well as flammability. 

A fire risk assessment includes conducting a thorough hazard identification. 

Hazardous Chemicals Data (416 items), 1975 491M, Manual of Hazardous Chemical Reactions (3550 items), 1975 704M, Recommended System for Identification of Fire Hazards of Materials, 1975... 

G.E. Hartzell, A.F. Grand, and W.G. Switzer, In Fire and Polymers Hazards, Identification and Prevention, Nelson, G.L. (Ed.) ACS Symposium Series, American Chemical Society, Washington, DC, 1990. 

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