Processing facilities protection systems

Ventilation System Blast Protection. The explosive containment rooms have the highest potential contamination level in the process facility. The punching and shearing that are part of the remote controlled disassembly operation result in the release of... 

Industrial fire protection and safety engineers attempt to eliminate hazards at their source or to reduce their intensity with protective systems. Hazard elimination may typically require the use of alternative and less toxic materials, changes in the process, spacing or guarding, improved ventilation or, spill control or inventory reduction measures, fire and explosion protective measures - both active and passive mechanisms, protective clothing, etc. The level or protection is dependent on the risk prevalent at the facility versus the cost to implement safety measures. 

Inherently design safety features at facilities provides for adequate spacing, arrangement and segregation of equipment from high hazard to low hazard. The least hazardous process systems should be used for obtaining the desired product or production objectives. Protective systems are provided to minimized the effects that may occur from a catastrophic incident. 

Whatever method is used, there should be a clear design philosophy for the basic process control system (BPCS) employed at a facility that is consistent throughout each process and throughout the facility. Consistency in application will avoid human factor errors by operators. The philosophy should cover measurements, displays, alarms, control loops, protective systems, interlocks, special valves (e.g., PSV,... 

Switchgear and relay rooms are required to have smoke detection per NFPA 850, section 5.8.4 and IEEE 979, section 2.7. The activation of the fire alarm should shut down the air handling system. If the facility is especially critical to the continued hydrocarbon process consideration of a fixed fire protection system should be evaluated. 

A Risk Management System (RMS) is vital for effective loss prevention. Fire protection is an essential part of an RMS. Appropriately designed, installed, and maintained fire protection systems are paramount to mitigating the direct consequences, and preventing the escalation, of fires in processing facilities. 

The first bullet indicates that the NFPA standards should be used to determine the fire water requirements for a facility. The NFPA standards do not define when a system is required. The first bullet does not achieve the result of defining when protection is necessary. In addition, the level of protection needed for a process facility is not covered by the cited NFPA standards. The NFPA standards simply describe howto design and install system components. 

It is not the intent of this Guideline to deal in depth with facility security issues. However, effective fire prevention in a processing facility depends on people in addition to systems to detect developing fires and other incidents and to detect unauthorized intrusion into the facility. Intruder-caused vandalism, damage, spills, releases, or fires are not common, but are a credible threat. The potential fire prevention and protection requirements to manage the risk of security events from terrorism need to be considered in the overall fire protection system design. 

Understanding fire hazards is essential to risk reduction and fire protection decision-making. A fire hazard analysis (FHA) is a tool used to understand fire hazards. The process of quantifying the fire hazard is typically motivated by the need to determine the overall hazard of a process or facility or to have a decision-making tool for fire protection systems (Chapter 6). An FHA is an important element of a risk assessment and can also be used as a stand-alone hazard evaluation tool. 

The company or facility should make use of the services of an engineer knowledgeable and trained in fire protection. Ideally, a registered fire protection engineer should be available to review fire protection designs. Fire safety, loss prevention, or process safety engineers should assist in the analysis of hazards, selection of protection system specifications, approval of the system, and acceptance testing. 

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. 

In the majority of applications in processing facilities handling flammable gases or liquids, or liquefied flammable gases, fixed water-based fire protection systems will control, but not extinguish, the fire. Foam-water sprinkler systems are an alternative to water sprinkler systems. Both water and foam-water sprinkler systems are discussed in Chapter 7. 

Since control rooms are normally constantly manned, it is considered unlikely that a fire could progress undetected to a hazardous size. Fixed fire protection systems, whether manually or automatically activated, are seldom installed in control rooms of processing facilities, mainly due to the fact that they are normally constantly manned. As such, it is considered unlikely that any fire that does occur would progress undetected to a size that cannot be extinguished by manual intervention (fire extinguishers, hose reel, etc.). 

Table 10-1 references the applicable NFPA code for the majority of the fire protection systems found in petrochemical and hydrocarbon processing facilities. 

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