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Fire detectors

The most important hardware items appeared to be the detectors themselves. The gas detection system gave frequent spurious alarms, and on both platforms the ultraviolet (UV) fire detectors were also prone to spurious activation from distant hot work for example, and had a limited ability to detect real fires. The tmreliability of these systems had a general effect on response time and would, overall, lengthen the time to respond. The second aspect which was related to hardware was fimction and performance testing of the emergency blowdown systems. It is critical that the workers believe the systems will work when required, and this can only be achieved by occasional use or at least fimction testing. [Pg.339]

Fire Aiarm ON/OFF Haion System ON/OFF Sprinkier System ON/OFF Fire Notices Posted YES/NO Insurance Informed YES/NO Fire Detectors are protected... [Pg.1071]

Arsenic and antimony are metalloids. They have been known in the pure state since ancient times because they are easily obtained from their ores (Fig. 15.3). In the elemental state, they are used primarily in the semiconductor industry and in the lead alloys used as electrodes in storage batteries. Gallium arsenide is used in lasers, including the lasers used in CD players. Metallic bismuth, with its large, weakly bonded atoms, has a low melting point and is used in alloys that serve as fire detectors in sprinkler systems the alloy melts when a fire breaks out nearby, and the sprinkler system is activated. Like ice, solid bismuth is less dense than the liquid. As a result, molten bismuth does not shrink when it solidifies in molds, and so it is used to make low-temperature castings. [Pg.745]

Safety Systems. A safety system is provided with built in safety shutdowns and emergency stop buttons. Crash buttons are located in the laser room, the laser table enclosure and the dome. The laser system is tied into the Observatory emergency stop system. Included both in the laser room and on the laser table are surveillance cameras, heat exchangers, alcohol sensors and fire detectors. In addition to personnel safety features, extensive interlocks have been installed in the laser to prevent the operator from inadvertently damaging it. [Pg.238]

In the present example, the only fire detector is in the fire room. When it alarms, the fire room occupant is awakened immediately, but occupants in the suite can hardly hear it. They are slow to respond. The program EXITT knows where all persons are, decides mother will get baby, seeks the shortest path to get there and calculates the time at 1.3 m/sec. Mother and baby then follow the shortest route to the corridor door. The times required for these actions are given in Table II. [Pg.75]

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. [Pg.2]

Combustible gases such as CH4, C2H6 (gas detection via flame detection (Europe), fire detectors, caravans with gas detectors)... [Pg.222]

Multi-sensor fire detectors provide faster detection with fewer false alarms. These sensors are capable of monitoring the environment for multiple purposes, e.g. carbon monoxide concentration, concentration of flammable gases and indoor air quality, too. [Pg.234]

When properly applied, ultraviolet detectors can serve as excellent fire detectors in munitions manufacturing. Detection times as fast as 10 milliseconds can be achieved while effectively resisting false alarms. [Pg.188]

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. [Pg.179]

Multi-band fire detector monitors monitor several wavelengths of predominate fire radiation frequencies by photocells. They compare these measurements to normal ambient frequencies through micro processing. Where these are found be above certain levels an alarm is indicated. False alarms may even be "recognized"... [Pg.182]

Fire detectors generally fall within one of three categories heat, smoke, and flame. Heat detectors work by sensing the heat from a fire. Smoke detectors sense the combustion products from the fire. Flame detectors identify flame by sensing the IR or UV light it emits. [Pg.187]

Fire detectors—dry-pilot head and pneumatic rate-of-rise heat detectors are the most frequent devices used. A dry pilot head detection systems uses 165°F (74°C) V2-in sprinkler head with air pressure maintained in the piping. When the sprinkler opens the air is released resulting in the sprinkler valve opening. Other types of detectors include ultraviolet, infrared flame detectors, or thermostatic cable heat detection. [Pg.205]

NFPA 72 E, Automatic Fire Detectors, National Fire Protection Association, Qunicy, MA, 1990. [Pg.13]

This means "Boiling Liquid Expanding Vapor Explosion" and characterizes the physical explosion of a liquefied gas/supercritical fluid that is brutally decompressed to atmospheric pressure, in case of pressure vessel rupture or opening. Catastrophic BLEVE occurred when liquefied petroleum gases vessels burst (Mexico, Feyzin,...), followed by the "chemical" explosion due to gas cloud inflammation. In fact, this hazard is directly linked to metal weakening in case of fire around the vessel(s). It is the reason why it is recommended to install fire detectors that could order immediate depressurization of the whole plant in case of fire. [Pg.629]

The fire detectors (fitted as an option) shall have an individual power supply and shall be explosion protected to enable their correct function in the OFF state of the p-apparatus... [Pg.146]

These next scenes are not sequences of an explosion, but of a burning torch being thrown into an open cublicle with an open pan of gasoline on the floor. In the cubicle is a UV fire detector and a 10-pound bottle of Halon 1301, an extinguishing agent. [Pg.180]


See other pages where Fire detectors is mentioned: [Pg.62]    [Pg.187]    [Pg.187]    [Pg.205]    [Pg.183]    [Pg.296]    [Pg.74]    [Pg.188]    [Pg.145]    [Pg.146]    [Pg.146]    [Pg.146]    [Pg.146]    [Pg.151]   
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See also in sourсe #XX -- [ Pg.532 ]

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Fire alarms and detectors

Fire alarms heat detectors

Fire alarms radiation detectors

Fire and gas detector

Fire detection methods flame detectors

Fire detection methods smoke detectors

Fire, Flame, and Smoke Detectors

IR fire detectors

Radiation detector requirements, fire

UV fire detectors

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