Fire safety design considerations

Ensure the adequacy (in terms of quality, quantity and reliability) of services/ufilities, e.g. steam, process/cooling water, electricity, compressed air, inert gas, fire suppression systems, ventilation. Stand-by or emergency services may be required. Some general safety design considerations are summarized in Table 12.11. 

Process Safety Considerations. Unit optimization studies combined with dynamic simulations of the process may identify operating conditions that are unsafe regarding fire safety, equipment damage potential, and operating sensitivity. Several instances of fires and deflagrations in ethylene oxide production units have been reported in the past (160). These incidents have occurred in both the reaction cycle and ethylene oxide refining areas. Therefore, ethylene oxide units should always be designed to prevent the formation of explosive gas mixtures. 

Flash point is one of the most important fire safety characteristics and hence it is a very important consideration in solvent design. The flammability limit of a solvent is characterized by its flash point, which is the temperature at which the mixture of air and vapor above the liquid can be ignited (Mullin, 1961). It is the lowest point at which the vapor pressure of a liquid will produce a flammable mixture. The flash point of the solvent can be estimated using the following group contribution method (ICAS, 2003)... 

NTSHIHARA, T., et al.. Safety Considerations and Countermeasures Against Fire and Explosion at an HTGR-Hydrogen Production System (Proposal of Safety Design Concept), (3rd JAERI Symp., Oarai, 1996), Proc. JAERI-Conf 96-010, Japan Atomic Energy Research Institute (1996) 264-271. 

There are other engineering factors that affect the fire and explosion hazard, e.g., engineering standards of the structural steel and foundations, process equipment, heat exchangers, feeding system, fan and blowers, storage vessels, electrical equipment, instruments, and fire protection and safety equipment. Considerable assistance in design also can be obtained from relevant codes of practice. The responsibility for safe operation rests with the manufacturers of equipment and products as required by national law (e.g.. Factories Act and Health and Safety at Work Act in the United Kingdom). 

Anania, T.L., and J.A. Seta. 1975. Lead Exposure and Design Considerations for Indoor Firing Ranges. HEW (NIOSH) 76-130. U.S. Department of Health, Education, and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, Cincimiati, OH [online]. Available http //www. cdc.gOv/niosh/docs/76-130/pdfs/76-130.pdf [accessed Apr. 24,2012]. 

The fire safety of equipment enclosed in cabinets could be controlled by consideration of the components and cables inside or by designing the cabinet in an appropriate way. In some cases active measures like detectors or water mist systems might be included. 

Modem fire protection techniques have developed through multidiscipline activities in science and engineering and involve careful selection of materials, end-use product design and manufacture, and fire performance and risk assessment. Reducing the flammability of materials is still an essential primary fire safety consideration. PP is an inherently flammable material and therefore flame retardant treatment of the polymer is an essential consideration in relation to fire safety. For material scientists, however, it is also very important to be aware of developments in fire safety science and engineering including the transition from prescriptive to functional regulation of fire safety in many coimtries. 

Safety equipment and safeguards (e.g., interlocks, system redundancy, failsafe design considerations, subsystem protection, fire suppression systems, PPE, and warning labels). 

Here we shall restrict consideration to safety and health considerations that can be built in while the design is developing rather than the detailed hazard and operability studies that take place in the later stages of design. The three major hazards in process plants are fire, explosion, and toxic release. ... 

A great deal of experimental work has also been done to identify and quantify the ha2ards of explosive operations (30—40). The vulnerabiUty of stmctures and people to shock waves and fragment impact has been well estabUshed. This effort has also led to the design of protective stmctures superior to the conventional barricades which permit considerable reduction ia allowable safety distances. In addition, a variety of techniques have been developed to mitigate catastrophic detonations of explosives exposed to fire. 

Safety Considerations Design and location of storage tanks, vents, piping, and connections are specified by state fire marshals, underwriters codes, and local ordinances. In NFPA 30, Flammable and Combustible Liquids Code, 1993 (published by the National Fire Protection Association, Quincy, Mass.), liquid petroleum fuels are classified as follows for safety in handhng ... 

Strength Habitability surveys conducted at CP (command post) upon arrival of Haz-Mat team. EPA conducted surveys at CP upon their arrival. SRS (Savannah River Site) and Richmond County Haz-Mat resources arrived on scene within a timely manner and were designated by FDIC (Fire Department Incident Commander) to be responsible for Haz-Mat operations. Haz-Mat personnel assisted in CP location determination. EPA utilized Coast Guard Gulf Coast Strike Team to provide monitoring and on scene response. By comparing consist (a list of all the cars in the train which describes their position in the train, type, contents, destination, etc.) to entry team visual inspection, chemicals involved were accurately identified. Written response plan and safety procedures implemented for Haz-Mat operations. Briefings provided to Haz-Mat responders by Safety Officer on entry considerations maps were covered for responders unfamiliar with the area. 

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