Flame detector - Revision history

Jan: Remove links to pages that do not exist; retain displayed text (wiki-wide link audit).

2026-11-02T21:32:50Z

Remove links to pages that do not exist; retain displayed text (wiki-wide link audit).

← Older revision		Revision as of 22:32, 2 November 2026
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	In explosion suppression systems, detectors, a power supply and control system and fast extinguishing units work together.<ref name="Zalosh-3-417" /> Dust explosion applications usually use pressure sensors, while gas explosion applications can use pressure sensors or ultraviolet detectors.<ref name="Zalosh-3-417" /> Of these, ultraviolet detectors give the fastest response.<ref name="Zalosh-3-417" /> The control system includes interlocks that monitor the system itself, shut down processes and trigger alarms when the system activates.<ref name="Zalosh-3-417" />		In explosion suppression systems, detectors, a power supply and control system and fast extinguishing units work together.<ref name="Zalosh-3-417" /> Dust explosion applications usually use pressure sensors, while gas explosion applications can use pressure sensors or ultraviolet detectors.<ref name="Zalosh-3-417" /> Of these, ultraviolet detectors give the fastest response.<ref name="Zalosh-3-417" /> The control system includes interlocks that monitor the system itself, shut down processes and trigger alarms when the system activates.<ref name="Zalosh-3-417" />

	Detectors in such plants may be installed where a flammable gas atmosphere can form, and one way to prevent an explosion there is to exclude ignition sources.<ref name="Beyler-2-181">Beyler (2002b), p. 2-181.</ref> Low-power equipment can be designed so that even its worst fault cannot release the minimum ignition energy of a given gas; such equipment is called intrinsically safe.<ref name="Beyler-2-181" /> Where this is not possible, the equipment can be housed in an explosion-proof enclosure that stops a flame from spreading out of it.<ref name="Beyler-2-181" /> The fuel oil tank room of World Trade Center 7 is an example. All its electrical devices were explosion proof, suitable for Class 1, Division 1, Group C in the [[hazardous area classification]] of the New York City building code.<ref name="GJ-27">Grill and Johnson (2005a), p. 27.</ref>		Detectors in such plants may be installed where a flammable gas atmosphere can form, and one way to prevent an explosion there is to exclude ignition sources.<ref name="Beyler-2-181">Beyler (2002b), p. 2-181.</ref> Low-power equipment can be designed so that even its worst fault cannot release the minimum ignition energy of a given gas; such equipment is called intrinsically safe.<ref name="Beyler-2-181" /> Where this is not possible, the equipment can be housed in an explosion-proof enclosure that stops a flame from spreading out of it.<ref name="Beyler-2-181" /> The fuel oil tank room of World Trade Center 7 is an example. All its electrical devices were explosion proof, suitable for Class 1, Division 1, Group C in the hazardous area classification of the New York City building code.<ref name="GJ-27">Grill and Johnson (2005a), p. 27.</ref>

	== Limits ==		== Limits ==

Lisa: Add Intermediate SVG figures with Fire Safety Academy watermark at planned locations; preserve article text

2026-11-02T17:13:43Z

Add Intermediate SVG figures with Fire Safety Academy watermark at planned locations; preserve article text

← Older revision		Revision as of 18:13, 2 November 2026
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	Fire detection devices operate in only one of three bands of the spectrum.<ref name="SMC-4-30" /> The SFPE Handbook gives ultraviolet as 0.1 to 0.35 micrometres, visible light as 0.35 to 0.75 micrometres and infrared as 0.75 to 220 micrometres.<ref name="SMC-4-30" /> Its table of fire signatures assigns the ultraviolet detector to radiation with a wavelength of 1700 to 2900 ångström, that is 0.17 to 0.29 micrometres.<ref name="SMC-4-4" /> A sensor reacts only to specific wavelengths, so the fuel must emit radiation within the sensor's band.<ref name="SMC-4-30" /> An infrared detector with a single sensor tuned to 4.3 micrometres, the emission peak of carbon dioxide, cannot be expected to detect a fire of a fuel that contains no carbon.<ref name="SMC-4-30" />		Fire detection devices operate in only one of three bands of the spectrum.<ref name="SMC-4-30" /> The SFPE Handbook gives ultraviolet as 0.1 to 0.35 micrometres, visible light as 0.35 to 0.75 micrometres and infrared as 0.75 to 220 micrometres.<ref name="SMC-4-30" /> Its table of fire signatures assigns the ultraviolet detector to radiation with a wavelength of 1700 to 2900 ångström, that is 0.17 to 0.29 micrometres.<ref name="SMC-4-4" /> A sensor reacts only to specific wavelengths, so the fuel must emit radiation within the sensor's band.<ref name="SMC-4-30" /> An infrared detector with a single sensor tuned to 4.3 micrometres, the emission peak of carbon dioxide, cannot be expected to detect a fire of a fuel that contains no carbon.<ref name="SMC-4-30" />

			[[File:fse-flame-detector-v1.svg\|thumb\|upright=1.5\|alt=Horizontal wavelength bar divided into ultraviolet, visible and infrared bands, with the UV detector band and the 4.3 micrometre carbon dioxide peak marked.\|The three bands used by flame detectors, with the ultraviolet detector band and the 4.3 µm carbon dioxide emission peak. Based on Schifiliti et al. (2002), pp. 4-4 and 4-30.]]

	== Types and selection ==		== Types and selection ==
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	As a worked example, the hangar case in the SFPE Handbook uses a detector that sees a 1.0 m² fire at 40 m on its axis.<ref name="SMC-4-32">Schifiliti et al. (2002), p. 4-32.</ref> In clear air, with the absorption term equal to one, halving the distance to 20 m makes the received power four times larger, because it scales with one over the distance squared. The other way round, a fire that emits only half the radiant power reaches the same signal only at 40/√2, about 28 m. Real air absorbs part of the radiation, so these clear-air values are upper limits for the reach of the detector.<ref name="SMC-4-31" />		As a worked example, the hangar case in the SFPE Handbook uses a detector that sees a 1.0 m² fire at 40 m on its axis.<ref name="SMC-4-32">Schifiliti et al. (2002), p. 4-32.</ref> In clear air, with the absorption term equal to one, halving the distance to 20 m makes the received power four times larger, because it scales with one over the distance squared. The other way round, a fire that emits only half the radiant power reaches the same signal only at 40/√2, about 28 m. Real air absorbs part of the radiation, so these clear-air values are upper limits for the reach of the detector.<ref name="SMC-4-31" />

			[[File:fse-flame-detector-v2.svg\|thumb\|upright=1.5\|alt=Falling curve of relative radiant power against distance from 10 to 60 m, equal to 1 at 40 m and 4 at 20 m.\|Relative radiant power at the detector against distance in clear air, set to 1 at 40 m. Halving the distance gives four times the power. Based on Schifiliti et al. (2002), pp. 4-31 to 4-32.]]

	The handbook then applies typical reductions to the detection distance of the hangar detectors, which have a field of view of 45 degrees.<ref name="SMC-4-32" /> A 30% loss of sensitivity at the edge of the field of view reduces the distance for the 1.0 m² fire from 40 m to 28 m.<ref name="SMC-4-32" /> A further loss of 3% at an ambient temperature of 50 °C gives about 26.8 m, and another 3% at 90% relative humidity gives about 25.6 m.<ref name="SMC-4-32" /> The largest viewing distance in the layout at 45 degrees is 20 m, so the design is considered valid.<ref name="SMC-4-32" /> Had the distance dropped below 20 m, a different layout or different devices would have been needed.<ref name="SMC-4-32" />		The handbook then applies typical reductions to the detection distance of the hangar detectors, which have a field of view of 45 degrees.<ref name="SMC-4-32" /> A 30% loss of sensitivity at the edge of the field of view reduces the distance for the 1.0 m² fire from 40 m to 28 m.<ref name="SMC-4-32" /> A further loss of 3% at an ambient temperature of 50 °C gives about 26.8 m, and another 3% at 90% relative humidity gives about 25.6 m.<ref name="SMC-4-32" /> The largest viewing distance in the layout at 45 degrees is 20 m, so the design is considered valid.<ref name="SMC-4-32" /> Had the distance dropped below 20 m, a different layout or different devices would have been needed.<ref name="SMC-4-32" />

			[[File:fse-flame-detector-v3.svg\|thumb\|upright=1.5\|alt=Hangar cross-section with flame detectors in the upper corners, their 45 degree fields of view and a 1 square metre pool fire on the floor.\|Infrared flame detectors in an aircraft hangar: the detection distance for a 1.0 m² fire falls from 40 m on axis to about 25.6 m at the edge of the view, still above the 20 m needed. Based on Schifiliti et al. (2002), pp. 4-31 to 4-32.]]

	== Design of a flame detection system ==		== Design of a flame detection system ==

Daan: FSE wiki: split a sentence over 35 words; footnote placement (written by Claude Opus 5.5)

2026-11-01T22:32:39Z

FSE wiki: split a sentence over 35 words; footnote placement (written by Claude Opus 5.5)

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	The SFPE Handbook describes the design in a fixed order.<ref name="SMC-4-31" /> First a detector type is chosen that matches the fuel. Then the possible sources of interfering radiation are identified and a device is selected that resists them.<ref name="SMC-4-31" /> Next, the manufacturer's data give the mounting height and lateral distance limits for the critical fire size.<ref name="SMC-4-31" /> The layout must then account for all obstructions so that every part of the space is watched.<ref name="SMC-4-31" /> Finally, the reductions in sensitivity due to viewing angle, temperature and humidity are checked against the actual viewing distances.<ref name="SMC-4-31" /><ref name="SMC-4-32" />		The SFPE Handbook describes the design in a fixed order.<ref name="SMC-4-31" /> First a detector type is chosen that matches the fuel. Then the possible sources of interfering radiation are identified and a device is selected that resists them.<ref name="SMC-4-31" /> Next, the manufacturer's data give the mounting height and lateral distance limits for the critical fire size.<ref name="SMC-4-31" /> The layout must then account for all obstructions so that every part of the space is watched.<ref name="SMC-4-31" /> Finally, the reductions in sensitivity due to viewing angle, temperature and humidity are checked against the actual viewing distances.<ref name="SMC-4-31" /><ref name="SMC-4-32" />

	The International Fire Engineering Guidelines describe a flame detector as a point that receives radiation from a flame with a specific flame temperature and emissivity.<ref name="IFEG-2.7-6" /> The intensity of the radiation it receives can be calculated with the methods for radiation from fires in the same guidelines.<ref name="IFEG-2.7-6" /> The sensitivity varies with the direction of the incoming radiation, and this off-axis sensitivity must be considered in design.<ref name="IFEG-2.7-6" /> A method for estimating flame height is also needed for the operation of flame detectors.<ref name="IFEG-2.4-6">National Research Council of Canada et al. (2005), p. 2.4-6.</ref> ~~Unlike heat and smoke detectors~~, ~~flame detectors are not covered by~~ the fixed detector criteria in C/VM2 (second edition, 2025) ~~in New Zealand, whose table gives activation criteria only for heat detectors, smoke~~ detectors ~~and sprinklers~~.<ref name="MBIE25-27">Ministry of Business, Innovation and Employment (2025b), p. 27.</ref>		The International Fire Engineering Guidelines describe a flame detector as a point that receives radiation from a flame with a specific flame temperature and emissivity.<ref name="IFEG-2.7-6" /> The intensity of the radiation it receives can be calculated with the methods for radiation from fires in the same guidelines.<ref name="IFEG-2.7-6" /> The sensitivity varies with the direction of the incoming radiation, and this off-axis sensitivity must be considered in design.<ref name="IFEG-2.7-6" /> A method for estimating flame height is also needed for the operation of flame detectors.<ref name="IFEG-2.4-6">National Research Council of Canada et al. (2005), p. 2.4-6.</ref> In New Zealand, the fixed detector criteria of C/VM2 (second edition, 2025) do not cover flame detectors.<ref name="MBIE25-27">Ministry of Business, Innovation and Employment (2025b), p. 27.</ref> Its table gives activation criteria only for heat detectors, smoke detectors and sprinklers.<ref name="MBIE25-27" />

	== Applications ==		== Applications ==

Daan: New FSE wiki article: Flame detector (written by Claude Opus 5.5)

2026-11-01T22:31:32Z

New FSE wiki article: Flame detector (written by Claude Opus 5.5)

New page

A '''flame detector''' is a fire detector that is activated by the electromagnetic radiation emitted by flames.<ref name="IS-F-30">Iqbal and Salley (2004), p. F-30.</ref> The common types sense ultraviolet (UV) or infrared (IR) radiation, and some units combine both.<ref name="IFEG-2.7-2">National Research Council of Canada et al. (2005), p. 2.7-2.</ref><ref name="Stroup-3-23">Stroup et al. (2016), p. 3-23.</ref> Unlike a [[smoke detector]] or a [[heat detector]], a flame detector does not wait for combustion products or hot gases to reach it.<ref name="SMC-4-4">Schifiliti et al. (2002), p. 4-4.</ref> It responds to radiation that travels in a straight line from the flame, so it must have a clear view of the fire.<ref name="SMC-4-30">Schifiliti et al. (2002), p. 4-30.</ref>

Flame detectors often start fast-response extinguishing or explosion suppression systems, which makes a reliable response within the required time essential.<ref name="SMC-4-30" /> The SFPE Handbook gives the example of infrared detectors that must find a 1 m² pool fire of jet fuel in a 20 m high aircraft hangar.<ref name="SMC-4-31">Schifiliti et al. (2002), p. 4-31.</ref> UV detectors give the fastest response of the detectors used to trigger suppression of gas explosions.<ref name="Zalosh-3-417">Zalosh (2002), p. 3-417.</ref> The range of a flame detector depends on the size of the fire, the distance, the angle to the detector's axis and the absorption of radiation by the air.<ref name="SMC-4-31" /> Designers therefore work with manufacturer curves of fire size against distance, which are based on the inverse square law.<ref name="SMC-4-30" /><ref name="SMC-4-31" /> For analysis and design, the International Fire Engineering Guidelines (2005) refer designers to the relevant standards, handbooks and manufacturer data.<ref name="IFEG-2.7-6">National Research Council of Canada et al. (2005), p. 2.7-6.</ref>

== How flame detectors work ==
Every fire detector senses one or more fire signatures. The SFPE Handbook lists these signatures as radiation, invisible and visible products of combustion, a rapid change in temperature and a high temperature.<ref name="SMC-4-4" /> Smoke detectors respond to the products of combustion and heat detectors respond to temperature.<ref name="SMC-4-4" /> Ultraviolet and infrared detectors are the only types in that list that respond to radiation.<ref name="SMC-4-4" /> A flame detector is therefore one part of a [[fire alarm system]] that can sense a fire at a distance, before any heat or smoke reaches the ceiling.<ref name="SMC-4-4" /><ref name="SMC-4-30" />

The radiation that a flame detector senses is the same [[thermal radiation]] that transfers heat from a fire. Radiation is emitted by the surface of a hot body, which can be a solid, a liquid or a gas body such as a flame or a smoke layer.<ref name="VR-5.4">Van Rossum (2027), §5.4.</ref> At the temperatures that matter in fires, most of this radiation lies in the infrared and part of it in the visible range; ultraviolet usually plays a small role in heat transfer.<ref name="VR-5.4" /> Gases between the fire and a receiving surface can absorb part of the radiation.<ref name="VR-5.4" />

Fire detection devices operate in only one of three bands of the spectrum.<ref name="SMC-4-30" /> The SFPE Handbook gives ultraviolet as 0.1 to 0.35 micrometres, visible light as 0.35 to 0.75 micrometres and infrared as 0.75 to 220 micrometres.<ref name="SMC-4-30" /> Its table of fire signatures assigns the ultraviolet detector to radiation with a wavelength of 1700 to 2900 ångström, that is 0.17 to 0.29 micrometres.<ref name="SMC-4-4" /> A sensor reacts only to specific wavelengths, so the fuel must emit radiation within the sensor's band.<ref name="SMC-4-30" /> An infrared detector with a single sensor tuned to 4.3 micrometres, the emission peak of carbon dioxide, cannot be expected to detect a fire of a fuel that contains no carbon.<ref name="SMC-4-30" />

== Types and selection ==
The International Fire Engineering Guidelines name ultraviolet and infrared flame detectors as the two main examples.<ref name="IFEG-2.7-2" /> Combination ultraviolet/infrared optical flame detectors also exist; they were among the devices tested in large US Navy aircraft hangars, 15 m and 22 m high.<ref name="Stroup-3-23" /> Fires of jet fuel in those tests ranged from 100 kW to about 33 MW.<ref name="Stroup-3-23" />

Selecting a sensor depends on the fuel, the growth rate of the fire, the ambient conditions and the control or extinguishing function that the detector must start.<ref name="SMC-4-30" /> The designer must also consider absorption of radiation by the air, other sources of radiation in the area, the size of the spark, ember or fire to be detected, and the distance to the sensor.<ref name="SMC-4-30" /> In the hangar example of the SFPE Handbook, infrared detection at 4.3 micrometres suits the carbon-based jet fuel.<ref name="SMC-4-31" /> Infrared detectors were also expected to cover a larger area per device than ultraviolet detectors and so to cost less in that case.<ref name="SMC-4-31" />

Sources of radiation that are not fires can cause false alarms. Resistance to such false responses can be obtained by filtering, by using several sensors in one unit, such as a two- or three-channel detector, or by both.<ref name="SMC-4-31" /> A system can also use coincident detection, in which two or more detectors must operate before an alarm is accepted.<ref name="IFEG-2.7-2" /> In explosion suppression, the choice between pressure sensors and ultraviolet detectors depends on the required response time and on concerns about spurious activation and about the detectors' view being blocked.<ref name="Zalosh-3-417" />

== Detection distance and the inverse square law ==
The radiant power that reaches a sensor falls quickly as the distance to the fire grows. Standard practice for the design of radiant energy detection is based on curves of fire size against distance, which are derived from the inverse square law.<ref name="SMC-4-30" /> The SFPE Handbook gives the relation as:<ref name="SMC-4-31" />

<math display="block">S = \frac{k\,P\,e^{-\zeta d}}{d^{2}}</math>

{| class="wikitable"
! Symbol !! Description !! Unit
|-
| <math>S</math> || radiant power reaching the detector || W
|-
| <math>k</math> || proportionality constant for the detector || –
|-
| <math>P</math> || radiant power emitted by the fire || W
|-
| <math>\zeta</math> || extinction coefficient of air || m<sup>−1</sup>
|-
| <math>d</math> || distance between the fire and the detector || m
|}

The handbook prints the exponential term without its minus sign.<ref name="SMC-4-31" /> The minus sign used here follows from the handbook's own statement that humidity and dust absorb radiation and so limit the radiation that reaches the sensor.<ref name="SMC-4-31" /> Manufacturers test a sensor with several fuels and plot the normalised fire size against the normalised distance.<ref name="SMC-4-31" /> The resulting curve gives the largest distance at which the sensor consistently detects a fire of a given size, usually stated in square metres of burning area.<ref name="SMC-4-31" />

As a worked example, the hangar case in the SFPE Handbook uses a detector that sees a 1.0 m² fire at 40 m on its axis.<ref name="SMC-4-32">Schifiliti et al. (2002), p. 4-32.</ref> In clear air, with the absorption term equal to one, halving the distance to 20 m makes the received power four times larger, because it scales with one over the distance squared. The other way round, a fire that emits only half the radiant power reaches the same signal only at 40/√2, about 28 m. Real air absorbs part of the radiation, so these clear-air values are upper limits for the reach of the detector.<ref name="SMC-4-31" />

The handbook then applies typical reductions to the detection distance of the hangar detectors, which have a field of view of 45 degrees.<ref name="SMC-4-32" /> A 30% loss of sensitivity at the edge of the field of view reduces the distance for the 1.0 m² fire from 40 m to 28 m.<ref name="SMC-4-32" /> A further loss of 3% at an ambient temperature of 50 °C gives about 26.8 m, and another 3% at 90% relative humidity gives about 25.6 m.<ref name="SMC-4-32" /> The largest viewing distance in the layout at 45 degrees is 20 m, so the design is considered valid.<ref name="SMC-4-32" /> Had the distance dropped below 20 m, a different layout or different devices would have been needed.<ref name="SMC-4-32" />

== Design of a flame detection system ==
Fire detection systems serve goals of life safety, property protection, business protection and environmental protection.<ref name="SMC-4-1">Schifiliti et al. (2002), p. 4-1.</ref> Detectors may also start other fire protection systems, such as special extinguishing systems and smoke control systems.<ref name="SMC-4-2">Schifiliti et al. (2002), p. 4-2.</ref> When a flame detector activates a fast extinguishing or control system, such as an explosion suppression system, it must respond reliably within the required time.<ref name="SMC-4-30" />

The SFPE Handbook describes the design in a fixed order.<ref name="SMC-4-31" /> First a detector type is chosen that matches the fuel. Then the possible sources of interfering radiation are identified and a device is selected that resists them.<ref name="SMC-4-31" /> Next, the manufacturer's data give the mounting height and lateral distance limits for the critical fire size.<ref name="SMC-4-31" /> The layout must then account for all obstructions so that every part of the space is watched.<ref name="SMC-4-31" /> Finally, the reductions in sensitivity due to viewing angle, temperature and humidity are checked against the actual viewing distances.<ref name="SMC-4-31" /><ref name="SMC-4-32" />

The International Fire Engineering Guidelines describe a flame detector as a point that receives radiation from a flame with a specific flame temperature and emissivity.<ref name="IFEG-2.7-6" /> The intensity of the radiation it receives can be calculated with the methods for radiation from fires in the same guidelines.<ref name="IFEG-2.7-6" /> The sensitivity varies with the direction of the incoming radiation, and this off-axis sensitivity must be considered in design.<ref name="IFEG-2.7-6" /> A method for estimating flame height is also needed for the operation of flame detectors.<ref name="IFEG-2.4-6">National Research Council of Canada et al. (2005), p. 2.4-6.</ref> Unlike heat and smoke detectors, flame detectors are not covered by the fixed detector criteria in C/VM2 (second edition, 2025) in New Zealand, whose table gives activation criteria only for heat detectors, smoke detectors and sprinklers.<ref name="MBIE25-27">Ministry of Business, Innovation and Employment (2025b), p. 27.</ref>

== Applications ==
The sources describe flame detectors in large hangars, in process plants and in explosion suppression systems. The SFPE Handbook uses an aircraft hangar of 50 m by 80 m with a 20 m ceiling, where a fuel spill fire must activate a fixed suppression system.<ref name="SMC-4-31" /> In the chemical process industries, smaller leaks may be detected by gas or flame detectors, if these are installed.<ref name="Barry-5-184">Barry (2002), p. 5-184.</ref> A quantitative risk assessment should then establish the position, effectiveness and reliability of these detectors.<ref name="Barry-5-184" /> It should also describe in detail how gas and flame detection start the emergency shutdown system.<ref name="Barry-5-182">Barry (2002), p. 5-182.</ref>

In explosion suppression systems, detectors, a power supply and control system and fast extinguishing units work together.<ref name="Zalosh-3-417" /> Dust explosion applications usually use pressure sensors, while gas explosion applications can use pressure sensors or ultraviolet detectors.<ref name="Zalosh-3-417" /> Of these, ultraviolet detectors give the fastest response.<ref name="Zalosh-3-417" /> The control system includes interlocks that monitor the system itself, shut down processes and trigger alarms when the system activates.<ref name="Zalosh-3-417" />

Detectors in such plants may be installed where a flammable gas atmosphere can form, and one way to prevent an explosion there is to exclude ignition sources.<ref name="Beyler-2-181">Beyler (2002b), p. 2-181.</ref> Low-power equipment can be designed so that even its worst fault cannot release the minimum ignition energy of a given gas; such equipment is called intrinsically safe.<ref name="Beyler-2-181" /> Where this is not possible, the equipment can be housed in an explosion-proof enclosure that stops a flame from spreading out of it.<ref name="Beyler-2-181" /> The fuel oil tank room of World Trade Center 7 is an example. All its electrical devices were explosion proof, suitable for Class 1, Division 1, Group C in the [[hazardous area classification]] of the New York City building code.<ref name="GJ-27">Grill and Johnson (2005a), p. 27.</ref>

== Limits ==
A flame detector is mainly a line-of-sight device.<ref name="SMC-4-30" /> A fire hidden behind equipment, stored goods or structure may not be seen, which is why the layout must consider all obstructions.<ref name="SMC-4-31" /> Sensitivity decreases as the fire moves away from the optical axis: a fire detectable at a given distance on the axis may not be detectable at the same distance 30 degrees off the axis.<ref name="SMC-4-31" />

The surroundings also matter. Humidity and dust absorb radiation, and a higher ambient temperature can lower the relative sensitivity of the sensor.<ref name="SMC-4-31" /> Even a small decrease can affect the response to the expected fire.<ref name="SMC-4-31" /> Other radiation sources in the area, or air that absorbs a large fraction of the radiation, may change the type, location and spacing of the sensors.<ref name="SMC-4-30" />

The detector also has to match the fuel. A sensor that reacts only to a narrow band, such as the carbon dioxide peak at 4.3 micrometres, will not detect fuels that do not emit in that band.<ref name="SMC-4-30" /> Finally, the performance data of flame detectors come largely from manufacturers.<ref name="SMC-4-31" /> The International Fire Engineering Guidelines therefore advise taking relevant standards, handbooks and manufacturer data into account in analysis and design.<ref name="IFEG-2.7-6" />

== See also ==
* [[Deluge system]]
* [[Beam smoke detector]]
* [[Multi-sensor detector]]
* [[Detector activation time]]
* [[Aspirating smoke detection]]

== Notes ==
<references />

== References ==
* Barry, T. F. (2002). Quantitative risk assessment in chemical process industries. In P. J. DiNenno, D. Drysdale, C. L. Beyler, W. D. Walton, R. L. P. Custer, J. R. Hall Jr., & J. M. Watts Jr. (Eds.), ''SFPE handbook of fire protection engineering'' (3rd ed., pp. 5-176–5-213). National Fire Protection Association; Society of Fire Protection Engineers.
* Beyler, C. L. (2002b). Flammability limits of premixed and diffusion flames. In P. J. DiNenno, D. Drysdale, C. L. Beyler, W. D. Walton, R. L. P. Custer, J. R. Hall Jr., & J. M. Watts Jr. (Eds.), ''SFPE handbook of fire protection engineering'' (3rd ed., pp. 2-172–2-187). National Fire Protection Association; Society of Fire Protection Engineers.
* Grill, R. A., & Johnson, D. A. (2005a). ''Documentation of the fuel system for emergency power in World Trade Center 7'' (NIST NCSTAR 1-1J). National Institute of Standards and Technology.
* Iqbal, N., & Salley, M. H. (2004). ''Fire Dynamics Tools (FDTs): Quantitative fire hazard analysis methods for the U.S. Nuclear Regulatory Commission Fire Protection Inspection Program'' (NUREG-1805). U.S. Nuclear Regulatory Commission, Office of Nuclear Reactor Regulation.
* Ministry of Business, Innovation and Employment. (2025b). ''Verification Method C/VM2: Framework for fire safety design'' (2nd ed.).
* National Research Council of Canada, International Code Council, Department of Building and Housing, & Australian Building Codes Board. (2005). ''International fire engineering guidelines'' (2005 ed.). Australian Building Codes Board.
* Schifiliti, R. P., Meacham, B. J., & Custer, R. L. P. (2002). Design of detection systems. In P. J. DiNenno, D. Drysdale, C. L. Beyler, W. D. Walton, R. L. P. Custer, J. R. Hall Jr., & J. M. Watts Jr. (Eds.), ''SFPE handbook of fire protection engineering'' (3rd ed., pp. 4-1–4-43). National Fire Protection Association; Society of Fire Protection Engineers.
* Stroup, D., Lindeman, A., McGrattan, K., Peacock, R., Overholt, K., Joglar, F., LeStrange, S., & Montanez, S. (2016). ''Verification and validation of selected fire models for nuclear power plant applications: Supplement 1'' (NUREG-1824, Supplement 1; EPRI 3002002182). U.S. Nuclear Regulatory Commission, Office of Nuclear Regulatory Research; Electric Power Research Institute.
* Van Rossum, E. (2027). ''Introduction to Fire Safety Engineering''. Fire Safety Academy.
* Zalosh, R. (2002). Explosion protection. In P. J. DiNenno, D. Drysdale, C. L. Beyler, W. D. Walton, R. L. P. Custer, J. R. Hall Jr., & J. M. Watts Jr. (Eds.), ''SFPE handbook of fire protection engineering'' (3rd ed., pp. 3-402–3-421). National Fire Protection Association; Society of Fire Protection Engineers.

[[Category:Detection & Alarm]]