Type of Fires

Liquid phosphate esters, eg, tricresyl phosphate [1330-78-5] are one of two types of fire-resistant hydraulic fluids (qv). Fire-resistant fluids account for less than 10% of the total fluids market. Phosphoms-based fluids generally are stable at high temperatures in addition to being fire resistant. Approximately 10,000 t of organophophoms compounds were used in hydraulic fluids in 1994. The manufacture of these materials consumed ca 4000 t of POCI3. 

FIG. 27-51 Representative types of fired heaters a) vertical-tube cylindrical with cross-flow-convection section (h) horizontal-tube cabin (c) vertical cylindrical, helical coil, from Berman, Chem. Eng. 85 98-104, June 19, 1978.)... 

In case of fire, use. . . (indicate in the space the precise type of fire-fighting equipment. If water increases the risk, add - Never use water)... 

The frequency of fire-induced core melt, calculated by averaging the observed frequency of the Browns Ferry type of fire over the experience of U.S. commercial nuclear power plants, was found to be lE-5 per reactor-year, or about 20% of the total core-melt probability e.slimated in the Reactor Safety Study. Kazarians and Apostolakis (1978) performed the same type of calculations under different assumptions and concluded that the frequency of core melt could be higher by a factor of 10. 

List and briefly discuss the various types of fire system equipment. 

Having discussed tlie fundamental cliaracteristics of fires in general and tlie different types of fire, we now e.xamine more closely fire accidents tliat occur in process pkuits. Specifically, we review plant fire classifications, sources, causes, damage potentials, and detection and protection systems. 

Two different types of fire protection systems can be considered ... 

Due to its cooling power, water is the most effective extinguishing agent for many types of fire. It is particularly suitable for fires in carbonaceous materials. Portable extinguishers provide a limited quantity of water using gas pressure. Extinguishers should have a nozzle fitted so that the direction of the jet can be properly controlled. 

Moist potassium peroxodisulphate was accidentally exposed to traces of potassium hydroxide. It combusted spontaneously, causing the installations to catch fire. It is impossible to put out a fire involving this peroxydic compound with carbon dioxide or extinguishing powders although these agents are suitable for fires of chemical substances. Only water, which is usually not recommended in this case, can put out this type of fire. 

Little is known about the toxicological significance of materials that may be adsorbed to the soot in various types of fires. 

It is theoretically possible, based on the assumption of the type of fire exposure (i.e., pool, jet, etc.) to calculate the heat effects from the predicted fire on every portion of petroleum facility. As of yet this extremely costly and cannot be performed economically for an entire facility. 

Smoke detectors are employed where the type of fire anticipated and equipment protection needs a faster response time than heat detectors. A smoke detector will detect the generation of the invisible and visible products of combustion before temperature changes are sufficient to activate heat detectors. The ability of a smoke detector to sense a fire is dependent on the rise, spread, rate-of-bum, coagulation and air movement of the smoke itself. Where the safety of personnel is a concern, it is crucial to detect a fire incident at its early stages because of the toxic gases, lack of oxygen that may develop, and obscuration of escape routes. Smoke detection systems should be considered when these factors are present. 

Heat detectors normally have a higher reliability factor than other types of fire detectors. This tends to lead to fewer false alarms. Overall they are slower to activate than other detecting devices. They should be considered for installation only where speed of activation is not considered critical or as a backup fire detection device to other fire detection devices. They have an advantage of suitability for outdoor applications but the disadvantage of not sensing smoke particles or visible flame from a fire. 

Before the need of fire protection measures is defined, the type of hydrocarbon fire exposure should be identified. By determining the type of fire expected, the adequacy of the fire protection measures based on the philosophy of protection for the facility, can be assessed. The easiest method to arrive at the protection requirements is to identify the materials and pressures involved in the process. Once this is accomplished, the most appropriate fire control or suppression mechanism can be identified from NFPA 325M. Tables 3 and 4 provides examples of a tabular format that can be used to document the fire control mechanisms that have been chosen. 

Fire detection/fire alarm systems consist of different types of fire detection devices and fire alarm systems. These systems may detect fire, heat, smoke, or a combination of any of these. For example, a typical fire alarm system might consist of heat sensors, which are located throughout a facility and which detect high temperatures or a... 

Guidance on how to develop different types of fire scenarios common to process facilities. 

The release of a flammable gas or liquid can lead to different types of fire scenarios. These are dependent on the material released, the mechanism of release, the temperature and pressure of the material, ambient conditions, and the point of ignition. Types of fires include ... 

It is important that the outside service company meet the facility pre-qualification criteria. As part of the selection process, it must be determined if the service company is knowledgeable and experienced in the types of fire protection systems they will be designing, installing, or maintaining. 

There are different types of fire and many different firefighting agents for combating them. An understanding of how these different types of firefighting agents are used in fire protection is important because their effectiveness can vary widely when applied to different types of fires. 

Each type of fire proofing system uses a different combination of materials with various physical and chemical properties. Selection of fireproofing materials... 

It is important to select detection devices that are appropriate for the type of fire most likely to occur. Failure to do so will result in either a very slow response or the possibility of a large number of spurious alarms. The latter should be particularly avoided where the detection system is used to activate a fixed fire extinguishing system. 

The type of fire alarm system should be chosen based on personnel resources available at the facility. For continuously staffed facilities, proprietary supervised systems are preferred. For facilities staffed less than continuously, remote supervised station or central station fire alarms system are usually considered. In these systems, alarms are monitored by an outside firm responsible for alerting appropriate personnel or by the local fire department. 

Table 8-11 (API 2021) provides guidance by tank type on the potential types of fires and some general comments.

The project plan should encompass all aspects of a fire protection system, such as the underground fire water distribution system, fire pumps, aboveground water header, valving and standpipes, structural support, and detection and alarm systems. All work on the fire protection system must be coordinated with other work activities at the site or in the operating unit. The recommended installation practices for the different types of fire protection systems are covered in consensus standards, such as NFPA. The installation process is illustrated in Figure 9-1. 

Establish inspections/tests required and frequencies for each type of fire protection equipment. 

The release of a flammable gas or the vaporization of a liquefied flammable gas can lead to different types of fire scenarios dependent on the release mechanism and the point of ignition. Figure 5-2 on page 53 illustrates the different outcomes expected from a gas release. If ignition of a gas release does not occur immediately at the origin of the release, then a gas cloud can develop (the same situation can also occur above flammable liquid spills). A delayed ignition of the gas cloud can result in a flash fire in which the premixed (fuel and air) gas cloud burns rapidly, typically in a matter of seconds. 

Various calculation tools and other types of fire models are available that do not fit neatly into the above categories. Among these are multicalculation packages, flame spread models, and glass breaking simulations. 

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