NFPA National Fire Protection equipment

A facility stores NFPA (National Fire Protection Association) Class 1B liquid in a diked atmospheric storage tank equipped with an external floating roof. 

Fig. 14. Outside battery limit (OSBL) equipment spacing. Minimum spacing for off-site equipment is in meters. Classifications of tankage are Class 1 high hazard, flash point below 38°C Class 2 low hazard, flash point above 38°C. NFPA = National Fire Protection Association. Safety standards are calculated...

There are several area classification standards such as API RP 500 (2012), API RP 505 (1997), NFPA (National Fire Protection Association) publication 70 (2013), NFPA publication 497, NFPA 70, and local standards in practice. They define classified areas surrounding the individual equipment, based on characteristics and probability of leaked/released liq-uid/gas/solids. This approach reduces fire/explosion risk due to the simultaneous occurrence of a flammable atmosphere and eleetrical ignition to an acceptable level. The project team can use an appropriate area classification standard acceptable to the company and local government authorities. 

NFPA 53 Recommended Practice on Materials, Equipment, and Systems Used in Oxygen-Enriched Atmospheres. National Fire Protection Association, Quincy, MA. 

Let s take the example of benzene, which at 12,000 ppm, is 100% LEL. The National Fire Protection Association (NFPA) states that equipment can operate, without LEL monitors or controls, if the LEL is less than 25% LEL. For benzene then, 25% LEL is equal to 3,000 ppm. This upper boundary becomes a dictating factor in the selection and design of the oxidation equipment. If the concentration is higher than 25% LEL, the NFPA requirements state that an LEL monitor is required. Using an LEL monitor, NFPA guidelines allow operation up to 50% LEL (a 2 1 safety factor). Thus, 100% LEL is explosive if the stream is at 25%, a factor safety of four exists. 

Purged and Pressurized Enclosures for Electrical Equipment, NFPA 496, National Fire Protection Association, Quincy, MA, 1982 Approval Standard Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II and III, Division 1, Hazardous Locations, Class No. 3610, Factory Mutual Research, Norwood, MA, Oct. 1979... 

Traditionally, inerts have been obtained from sources such as high-pressure gas cylinders or tube trailers or through evaporation of cryogenic liquids from bulk tanks. Other sources of inerts include (NFPA 69, Standard on Explosion Prevention Systems, National Fire Protection Association, 2002 FM Global, Loss Prevention Data Sheet 7-59, Inerting and Purging of Tanks, Process Vessels, and Equipment, 2000)... 

National Fire Protection Association (NFPA), NFPA 496. Standard for Purged and Pressurized Enclosures for Equipment. NFPA Quincy, MA, 1993. 

In its NEP, OSHA points out that for workplaces not covered by 1910.272, but where combustible dust hazards exist within dust control systems or other containers, citations under section 5(a)(1) of the OSH Act (the General Duty Clause) may generally be issued for deflagration (fire) or explosion hazards. National Fire Protection Association (NFPA) standards should be consulted to obtain evidence of hazard recognition and feasible abatement methods. Other standards are applicable to the combustible dust hazard. For example, if the workplace has a Class II location, then citations under 29 CFR 1910.307 may be issued to those employers having electrical equipment not meeting the standard s requirements. 

The use of electrical equipment in hazardous areas is covered by the National Electrical Code, NEPA 70 (2006), National Fire Protection Association standards NFPA 496 (2003) and NEPA 497 (2004), and OSHA standard 29 CFR 1910.307. The American Petroleum Institute Recommended Practices API RP 500 (2002) and API RP 505 (1997) should also be consulted. 

NFPA 70B (2006) Recommended practice for electrical equipment maintenance. (National Fire Protection Association). 

NFPA. 1986. Manual for classification of gases, vapors, and dusts for electrical equipment in hazardous (classified) locations. Quincy, MA National Fire Protection Association, NFPA publication no. 497M. 

An explosion is defined in the National Fire Protection Association (NFPA) Fire Protection Handbook as a rapid release of high-pressure gas into the environment. This release of high-pressure gas occurs regardless of the type of explosion that has produced it. The high-pressure energy is dissipated by a shock wave that radiates from the blast center. This shock wave creates an overpressure in the surrounding area that can affect personnel, equipment, and structures (see Figure 3.2). An overpressure of just 0.5 to 1 psi can break windows and knock down personnel. At 5 psi, eardrums can rupture and wooden utility poles can be snapped in two. Ninety-nine percent of people exposed to overpressures of 65 psi or more would die. 

The National Hectrical Code (NEC) covers the safe and proper installation of wiring, electrical devices, and equipment in private and public biuldings. NEC is published by the National Fire Protection Association (NFPA) every three years. As an example of an NEC provision, the receptacle oudets in a room in a dwelling should be placed such that no point on the wall space is more than 6 ft away from the outlet in order to minimize the use of extension cords. After performing a Web search or obtainii a copy of the NEC handbook, give at least three other... 

All laboratories should have access to a qualified technician who can make routine repairs to existing equipment and modifications to new or existing equipment so that it will meet acceptable standards for electrical safety. The National Fire Protection Association s National Electrical Code Handbook (NFPA, 1993) provides guidelines. 

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