Fire detection systems

The OREDA Offshore Reliability Data Handbooks covers a variety of components used in offshore oil drilling and platforms, including gas/fire detection systems, process alarm systems, firefighting systems, pressure relieving systems, general alarm and communication systems, evacuation systems, process systems (vessels, valves, pumps, heat exchangers, and compressors), electrical and utility systems, and drilling equipment. 

Withdrawn) 1987 AMD 3 Portable fire extinguishers (AMD 8585) dated 15 December 1995. Withdrawn, superseded by BS 7863 1996, BS 7867 1997 and BS EN 3-1 to 6 (Withdrawn) 1977 Components of automatic fire detection systems. Part 1 Introduction. Withdrawn, superseded by BS EN 54-1 1996... 

AMD 1 Components of automatic fire detection systems. Part 5 Heat sensitive detectors point detectors containing a static element (AMD 5762) dated 31 August 1988. Superseded BS 3116 Part 1 1970... 

Libberton, G. P., A. Bendell, L. A. Walls, and A. G. Cannon. Some Problems Associated with the Collection of Data for Automatic Fire Detection Systems on a Large Industrial Site. Proc. I Mech. E. Conference on Data Collection and Analysis for Reliability Assessment. London, England, 1986. 

Fire override to open ventilators automatically by means of a connection to the fire-detection system or fireman s switch. This normally overrides all other control settings ... 

Fire detection For efficient operation, control of the ventilation must be linked to a fire-detection system or sprinkler flow switch to ensure that the ventilators are operated as early as possible. Natural ventilators must... 

Security and safety Intruder alarm Security systems Fire detection systems, with sensors for - temperature - toxic gases like CO, C02, exhaust gases, smoke, etc. - combustible gases like CH4, C2H6 flame detection, fire detectors, caravans with gas detectors, etc. 

When dealing with an entire fire detection system that utilizes more than one type of detector, a Detonator Module greatly expands the flexibility and capability of the system. An individual Detonator Module can accept multiple inputs from UV and IR controllers, other Detonator Modules, manual alarm stations, heat sensors, smoke detectors or any contact closure device. In the event of a fire, any of these devices will cause the internal fire circuitry of the module to activate the detonator circuit, sound alarms, and identify the zone that detected the fire. When properly used, a Detonator Module will add only one millisecond to the total system response time. See Figure 8 for an illustration of a fire detection system with a Detonator Module. 

Figure 8. Fire Detection System with Detonator Module...

Careful attention must also be paid to ensuring that no air bubbles are in the water piping, that the fastest possible water valves are utilized, and that the water nozzles are also as close as possible to the potential hazard to minimize the travel time of the water. These considerations will improve speed of response of the fire detection system to a much greater degree than improving the speed of the detector alone. 

Halon systems were the ideal fire suppression agent before their implications of environmental impact due to ozone depletion. The industry is gradually phasing out usage of halon systems for this reason. A flowchart to analyze mechanisms to supplement or eliminate Halon systems for electrical or computer processing areas is shown in Figure 11. Some of the prime reasons to eliminate the use of Halon systems is that the facility may be constantly manned with a relatively low fire risk. Other facilities may have a very low combustible load and can be supplemented by highly sensitive fire detection means, such as a VESDA fire detection system. 

Alarm systems can be integrated with fire detection systems, intrusion detection systems (IDSs), access control systems, or closed circuit television (CCTV) systems, so that these systems automatically respond when the alarm is triggered. For example, a smoke detector alarm can be set up to automatically notify the fire department when smoke is detected, or an intrusion alarm can automatically trigger cameras to turn on in a remote location so that personnel can monitor that location. 

The fire alarm and detection control panel is the central point of the fire detection system. This panel should be capable of ... 

Fire detection system circuits should be completely supervised as described below ... 

The principal difference between a pre-action system and a standard dry pipe system is that in the pre-action system, the water supply valve is actuated independently of the opening of the sprinklers. The water supply valve is opened by the operation of an automatic fire detection system, which immediately allows water to enter the overhead piping. Then, when the fire generates enough heat to fuse the sprinkler head, water is immediately discharged on the fire as with a wet pipe system. This system reduces the inherent time lag of a dry pipe system, but can still be used in unheated areas. An example of a pre-action system is shown in Figure 7-26. 

Any suitable fire detection system can be utilized to actuate the control valve. Since any other fire detection device is likely to operate faster than a sprinkler head, it is common for waterto have reached the sprinkler by the time... 

Where the need for fire detection is identified, the required performance of the fire detection system is already specified as part of the grading process. Fixed fire detection is typically installed to protect equipment that is high value, long lead time, or likely to be significant fire escalation hazards. The performance specification defines fire size and response time thresholds for alarm and action(s). Fire hazards are defined by radiant heat output (RHO). RHO gives a reasonable indication of the potential damage and the probability that the fire will escalate or cause loss. The RHO should not be used to determine fire thermal loading onto equipment and structures. Table 8-3 compares RHO and flame area for some typical hydrocarbon fires. 

LNG carriers are equipped with gas and fire detection systems. The cargo safety system is extensively instrumented - including a shut down system that is activated on predetermined parameters. Furthermore, the safety equipment of LNG carriers includes sophisticated radar and positioning systems that alert the crew to the surrounding traffic on potential hazards. A number of distress systems and beacons will automatically emit signals if the ship enters difficulty positions [10]. 

Design optimization studies provided a fire detection system employing minimum water which will effectively prevent between-bay flame propagation in the event of a process fire. The cost of installing quick-acting mechanical fire gates was avoided without affecting system safety of the CASBL. 

There are UV fire detection systems available that have the capability of self-examination for failures. This supervisory circuit is referred to as Automatic Optical Integrity. 

To prove this, the bilge water was allowed to rise above the top of the pumps and other major obstructions. Additional unsuppressed tests were conducted and the pressure rise was much slower as suspected in an unobstructed area. This proved that pressure sensors can be used in empty spaces but not in obstructed large spaces. At this point the pressure sensors were no longer used and the UV fire detection systems were now used. 

Luck, Heinz 0. and Schlossarek, Udo "Software Controlled Fire Detection Systems". Fire Science and Technology, Vo. 7,... 

In the BN-600 several leak and fire detection system types are used, namely ... 

Operation experience of sodium leak and fire detection systems indicate that design solutions on these systems have been made properly. 

Fire detection systems used in the process industries are listed in Table 12.4, along with a summary of the advantages and disadvantages of each. 

Figure 6-2 Firefighter Training Fire Detection Systems...

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