The selection of fire detectors shall comply with the following provisions:
1, the initial fire has a flame phase, producing a large amount of smoke and a small amount of heat, little or no flame radiation site, should choose smoke fire detector.
2, the rapid development of fire, can produce a large amount of heat, smoke and flame radiation sites, you can choose the temperature-sensitive fire detector, smoke fire detector, flame detector or its combination.
3, the rapid development of fire, there is a strong flame radiation and a small amount of smoke, heat, should choose a flame detector.
4, the initial fire has a negative phase, and the need for early detection of the site, it is advisable to add carbon monoxide fire detectors.
5, the use, production of flammable gas or combustible vapor sites, should choose flammable gas detector.
6, according to the protection site may fire site and combustion material analysis, as well as the type of fire detector, sensitivity and response time, such as select the corresponding fire detector, the formation of fire characteristics of unpredictable sites, according to the results of simulation tests can be selected fire detector.
7, the same detection area set up more than one fire detector, you can choose a complex to judge the fire function of the fire detector and fire alarm controller.
2, point fire detector selection
First, for rooms of different heights, you can select the point fire detector according to the table below.
Second, the following places should choose point-type smoke fire detectors:
1, hotels, hotels, teaching buildings, office buildinghalls, bedrooms, offices, shopping malls, train passenger carriages and so on.
2, computer room, communication room, film or television screening room.
3, stairs, walkways, elevator rooms, garages and so on.
4, library, archives, etc.
Third, meet one of the following conditions of the site, it is not appropriate to select point-type ion smoke fire detector:
1, the relative humidity is often greater than 95%.
2, air flow speed is greater than 5m/s.
3, a large number of dust, water mist stranded.
4, may produce corrosive gases.
5, under normal circumstances there is smoke stranded.
6, the production of alcohols, ethers, ketones and other organic substances.
Fourth, meet one of the following conditions of the site, it is not appropriate to choose a point-type photoelectric smoke fire detector:
1, a large number of dust, water mist stranded.
2, may produce steam and oil mist.
3, high altitude.
4, under normal circumstances there is smoke stranded.
V. Where one of the following conditions is met, it is advisable to select a point-type temperature-sensitive fire detector, and the appropriate category of temperature-sensitive fire detector should be selected according to the typical application temperature and maximum application temperature of the place of use:
1, the relative humidity is often greater than 95%.
2, smoke-free fire may occur.
3, a large amount of dust.
4, smoking room, etc. under normal circumstances there is smoke or steam stranded places.
5, kitchen, boiler room, generator room, drying workshop and other places not suitable for the installation of smoke fire detectors.
6, the need to jointly extinguish the "safe exit" sign light safety exit inside.
7, other no one stranded and not suitable for the installation of smoke fire detectors, but in the event of a fire need to timely alarm site.
6. Places where a fire may be caused or a fire that does not cause major losses in time, it is not appropriate to select a point-type temperature-sensitive fire detector;
7. Where one of the following conditions is met, it is advisable to select a point-type flame detector or an image-type flame detector:
1, fire when there is strong flame radiation.
2, may occur liquid combustion and other non-burning stage of the fire.
3, the need for a rapid response to the flame.
Eight, meet one of the following conditions of the site, it is not appropriate to select point-type flame detector and image-type flame detector:
1, before the flame appeared, there was smoke spreading.
2, the detector lens is easy to be contaminated.
3, the detector's "line of sight" is easily blocked by oil mist, smoke, water mist and ice and snow.
4. The combustibles in the detection area are metal and inorganic.
5, detector seislum is vulnerable to sunlight, incandescent lamps and other light sources directly or indirectly.
Nine, the detection area normally has high temperature objects, it is not appropriate to choose a single-band infrared flame detector.
Ten, under normal circumstances there is open fire operation, detector is susceptible to X-rays, arc light and lightning and other places, should not choose ultraviolet flame detector.
Xi, the following places should choose flammable gas detectors:
1, the use of flammable gas site.
2, gas stations and gas meter houses and storage of liquefied petroleum gas tanks.
3, other places that emit flammable gases and combustible vapors.
12. Point-type carbon monoxide fire detectors can be selected at the following sites where carbon monoxide is produced in the early stages of a fire:
1, smoke is not easy to convective or roof under the hot barrier place.
2, on the roof of the shed can not install other point fire detector situ.
3, the need for multi-signal composite alarm site.
Thirteen, more dirt and must be installed smoke fire detector site, should choose intermittent inhalation of the point-type sampling inhaling smoke fire detector or with the filter and line self-cleaning function of the pipeline sampling inhaling smoke fire detector.