Fire resistance standards

In the GDR, building structures are characterized not only in terms of fire resistance (standard TGL 10685/13-1981) but also for the degree of fire spreading (standard TGL 10685/12-1978). 

Sealants are now available which have enhanced fire resisfance. The fire-resistance standards commonly referenced are BS 476-20 19873 and BS 476-22 1987.36 The maximum fire resistance quoted in BS 476 is four hours. 

Some of the tests and criterion used to define fire resistance may be found in the Hterature (9). Additionally, the compression—ignition and hot manifold tests as defined in MIL-H-19457 and MIL-H-5606, respectively the Wick test as defined by Federal Standards 791, Method 352 flash point and fire point as defined in ASTM D92 autoignition temperature as defined in ASTM D2155 and linear flame propagation rate are defined in ASTM D5306 are used. 

U.S. Bureau of Mines, Fire Resistant Hydraulic Fluids, Schedule 30, Dec. 11, 1959 Eactory Mutual Research Approved Standard Eess Ha ardous... 

In addition to spacing criteria, many standards provide requirements for building design and construction to provide fire resistance and protect occupants. Table 3.2 summarizes typical key references for fire protection and evaluation. 

Time-temperature curves for fire resistance for different types of materials are available from American Society for Testing and Materials (ASTM) Standard E 119 (Ref. 41). 

Fire resistance is naturally weak. Standard grades burn easily generating flames, even after the ignition source is removed. Moreover, polyethylene drips while burning. 

The material and its installation should be designed to protect for a specific time period. For hydrocarbon fire exposure materials and their installation are generally tested to either UL 1 709 or ASTM El 529 to determine time-to-failure of different thicknesses and installation methods. It should be noted that the fire resistance rating is a measure of the ability of the installed material to withstand a specific "standard" fire. While these conditions closely match those in any given hydrocarbon fire, during actual fires the material may be exposed to conditions that may be more or less thermal intense, thus it can be expected to retain its integrity for a greater or lesser time. 

U L 2080, Standard for Fire Resistant Tanks for Flammable and Combustible Liquids... 

SwRI 93-01, Testing Requirements for Protected Aboveground Flammable Liquid/Fuel Storage Tanks, includes tests to evaluate the performance of ASTs under fire, hose stream, ballistics, heavy vehicular impact, and different environments. This standard requires pool-fire resistance similar to that of UL 2085. 

SwRI 97-04, Standard for Fire Resistant Tanks, includes tests to evaluate the performance of ASTs under fire and hose stream. This standard is similar to UL 2080 in that the construction is exposed to a 2-h hydrocarbon pool fire of 1093°C (2000°F). However, SwRI 97-04 is concerned only with the integrity of the tank after the 2-h test and not concerned with the temperature inside the tank due to the heat transfer. As a result, UL 142 tanks have been tested to the SwRI standard and passed. Secondary containment with insulation is not necessarily an integral component of the system. 

As stated earlier, shop-fabricated ASTs are often categorized according to the standards to which the tanks are fabricated, e.g., a UL 142 or UL 2085 tank. That said, however, there are defined categories such as diked tanks, protected tanks, fire-resistant tanks, and insulated tanks. It s critical, then, for the tank buyer or specifier to know precisely what is required or desired given the application, code requirements, and/or owner/operator preferences—and to discuss this with the tank contractor and/or manufacturer. 

An insulated tank can be a protected tank, built to third-party standards UL 2085 and/or SwRl 93-01, or a fire-resistant tank built to UL 2080 or SwRI 97-04. Protected tanks were developed in line with NFPA requirements and terminology, while fire-resistant ASTs were developed in line with Uniform Fire Code (now International Fire Code) requirements and terminology. Both protected tanks and fire-resistant tanks must pass a 1093°C (2000°F), 2-h fire test. 

There are no ISO, ASTM or British fire test method standards specifically for solid mbbers and there is no active fire test work being pursued in TC 45. There are, however, a number of published international test methods for cellular materials and plastics, the majority of which could be applied to rubbers. A comprehensive account of fire testing of plastics has been given by Paul in the Handbook of Polymer Testing81. There may be fire resistance requirements for particular rubber products and some examples were given by Schultz110. 

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