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Detector Information
SEC-K
Detector Location
Detector location will vary dependant on the individual characteristics of the target gas that is being monitored for. The descrip-
tions below describe the position for each detector after considering these characteristics.
Natural Gas
Natural gas detectors should be mounted at high level on a wall approximately 150mm from the ceiling height and avoiding
corners and potential dead air areas.
Natural gas detectors should not be mounted below the height of the top of a doorway for example. This is because as the
gas is slightly lighter than air it will rise filling the room from the ceiling down and will spill through the top of a door opening
into the next room. If the detectors are mounted below this height then it will take longer the gas to reach the detector.
LPG
LPG gas is heavier than air so detectors need to be mounted at low level 100mm from the floor, consideration should be given
to any potential mopping or wet floor height.
Carbon Monoxide
Carbon Monoxide is similarly weighted to air so detectors should be mounted between 1 to 2 meters from the floor.
Carbon Dioxide
Classroom
Carbon Dioxide detectors under guidance from IGEM/UP11/Edition2 should be mounted at a seated head height.
However following onsite experience this mounting height can make detectors susceptible to false readings due to direct
breath contact. We would suggest following the guidance for mounting as per a commercial kitchen to reduce the potential for
false alarm readings.
Commercial kitchen
Carbon Dioxide detectors should be installed so they monitor the general level of CO2 within the cooking
area. They should be mounted above standing head height and between 1m and 3m from the cooking line. Care should be
taken so they are not located close to the edge of a canopy or in direct flow of the supply or extract ventilation.
For additional information or guidance on site specific requirements please don’t hesitate to contact us.
Detector Testing
Any installed gas detector can be tested by allowing a small amount of the target gas onto the detector head until a change of
state is registered on the control panel.
If the level of gas applied is of the set low alarm level, the LED on the detector will change from a solid green to a flashing red.
An LED* or LCD* message indicating a low level alarm detection combined with an audible alarm on the panel will begin.
If the level of gas drops below the set low alarm level the detector LED will return to a solid green and the panels audible alarm
and LED* or LCD* message will clear.
Should an emergency shut-off valve be connected to the panel this will remain open during a low alarm level detection.
If the level of gas applied is of the high alarm level or above, the LED on the detector will change from a solid green to a solid
red. An LED* or LCD* message indicating a high level alarm detected combined with an audible alarm on the panel will begin.
Should an emergency shut-off valve be connected to the panel this will automatically close.
Once the level of gas drops below the high alarm level the audible alarm will continue and the high alarm LED* or LCD* mes-
sage will remain.
The valve cannot be reinstated until the gases have been cleared and the control panel reset.
*LED, LCD or both visual outputs will change dependant on the control panel connected.
