Fire design methods

The European classification system of reaction to fire must reflect the behaviour of tested products in real fires. Test methods should be designed so that the results can be used as important part of risk assessment. 

For any fire or combustion explosion to occur, three conditions must be met (as shown in the fire triangle of Figure 6-1). First, a combustible or explosive material must be present. Second, oxygen must be present to support the combustion reaction. Finally, a source of ignition must be available to initiate the reaction. If any of the three conditions of the fire triangle is eliminated, the triangle is broken and it is impossible for a fire or combustion explosion to result. This is the basis for the first six design methods listed above. 

A passive fire protection system requires no action to occur for it to function per its design intent. Examples of passive fire protection methods are fireproofing, spill containment, and physical separation of units and buildings. 

Designing plant safety systems so that redundant safety equipment is protected by automatic fire suppression systems and separated from each other and from other plant areas by fire barriers such that a fire would not endanger other safety related equipment required for safe shutdown. Alternate or dedicated shutdown capability should be provided where the protection of safety systems required for safe shutdown is not provided by established fire suppression methods. 

When fire engineering methods are used to determine fire resistance, the actions may be those appropriate to accidental design situations for which... 

Active methods of fire design are principally involved with fire safety and are applicable to all materials, not only FRP composites. 

P(4) Systems and methods adopted in fire design for fire penetration shall provide adeqnate fire barriers around pipes, services and other perforations throngh the FRP composite components. 

P(8) in developing methods and systems for fire design of FRP composites, the designer shall consider the effects on other design properties of the materials and of the structure. Such design properties shall include ... 

A. 1008. A description and a safety analysis of the fire protection system shall be provided in this section, including information on procedures and maintenance activities. Reference could also be made to the design methods (para. A.211). 

Employers must ensure that proper safety precautions are in place for all of the fuel and powered sources that would be used to power a lift truck. Manufacturers or their representatives must be consulted for safety guidelines in the design, construction, and everyday use of any fuel or battery. Consult the NFPA, FM, or OSHA codes for guidance. Personal protective equipment, fire-protection methods, and emergency plans must be in place to protect workers and property. 

The most extensive body of tests are provided under the auspices of ASTM Standard methods. Specific ASTM test designations and descriptions are available (48). The other compendium of fire-retardant tests are contained ia Federal Test Method Standards 191A (49). 

Fire and Explosion Prevention. Prevention of fire and explosion takes place in the design of chemical plants. Such prevention involves the study of material characteristics, such as those in Table 1, and processing conditions to determine appropriate ha2ard avoidance methods. Engineering techniques are available for preventing fires and explosions. Containment of flammable and combustible materials and control of processes which could develop high pressures are also important aspects of fire and explosion prevention. 

Equation (12-57) does not account for gas radiation at high temperature when the kiln charge can see the burner flame hence, the method will yield a conservative design. When a kiln is fired internally, the major source of heat transfer is radiation from the flame and hot gases. This occurs directly to both the sohds surface and the wall, and from the latter to the product by reradiation (with some conduction). 

Bv this method, in general, the expecl ed inherent maximum explosion overpressure of the order P = 7 to 10 bar will be reduced to a value of Pred.max < 2 bai. In this case, the static activation overpressure of the venting device is < 0.1 bar. The resulting P,ed,max i i y not exceed the design pressure of the equipment. The explosion as such is not prevented only the dangerous consequences are limited. However, subsequent fires must be expecl ed. 

These refer to the control of a chemical process and include planning for familiar tasks (e.g., change type of fuel-firing in a furnace) or planning for familiar but infrequent tasks (e.g., start-up or shutdown a furnace). Methods of task analysis and error analysis can be used to analyze well-established strategies that operators use to perform procedural tasks and identify the user s information needs. An implication for display design would be that all information needed... 

Gas-fired water heaters use the same general method of construction, except that the elements are replaced with a burner beneath the tank. The combustion products from the burner are vented through a flue made out of the same thickness steel as the tank, that goes up through the center of the tank. To increase heat transfer from the hot flue gases to the inner wall of the flue, a baffle is inserted down the flue. This baffle is a twisted strip of sheet metal with folds and tabs on it. The folds and tabs are designed to... 

Gas-Fired water heaters are also made more efficient by a variety of designs that increase the recov-ei y efficiency. These can be better flue baffles multiple, smaller-diameter flues submerged combustion chambers and improved combustion chamber geometry. All of these methods increase the heat transfer from the flame and flue gases to the water in the tank. Because natural draft systems rely on the buoyancy of combustion products, there is a limit to the recovery efficiency. If too much heat is removed from the flue gases, the water heater won t vent properly. Another problem, if the flue gases are too cool, is that the water vapor in the combustion products will condense in the venting system. This will lead to corrosion in the chimney and possible safety problems. 

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