QFM440 Wall Mounted CO2 Monitoring and Alarm System

Easy-to-install, wall mounted, modular carbon dioxide concentration monitor and warning alarm system, providing continuous monitoring of carbon dioxide concentration in the surrounding air and both visual and audible alarms when these fall outside pre-set levels.


The QFM440 Carbon Dioxide Monitor may be used as a stand-alone device with its own audible and visual alarms, or linked to other repeater modules to mimic the condition of the monitor. Repeater modules can be connected to the QFM440 and located outside the monitored area to warn users at the point of entry. The system can be fully customised to allow multiple location monitoring and further modules can be added at a later date to expand the scope of the system.

Key Features
  • Monitor operates continuously and cannot be switched off, giving maximum user protection.
  • Built in visual and audible alarms with separate ‘HIGH’ and ‘CRITICALLY HIGH’ alarm states.
  • Internal audible alarm is 85dBA at 30cm.
  • Long life carbon dioxide sensors provide 10 years operation in normal use, based on yearly service and calibration.
  • Simple & secure connections to repeater modules using a pre-wired plug in connector (up to a maximum of 100m).
  • Relay connection for fans, valves or other alarm devices to allow the user to fully customise the system to preferred requirements (see model QFM440/R).
  • Supplied with a plug in the wall 12V DC power supply unit, we receommend that a backup power supply is used to the power the monitor. 

NB Carbon dioxide monitors must not be used for the detection of oxygen gas

Dimensions H150 ×W90 ×D50mm
Weight (excl. cable) 550g
L.E.D’s Warning alarm, critical alarm, power indication, low battery indication, service
Alarm indication Audible - 85dBA at 30cm
Calibration test Test switch (RED flashing LEDs + audible bleep)
Indications and Alarms High CO2 (1.5%)*
Critically High CO2 (3.0%)*
Warning alarm (Red flashing LED + audible bleep)
Critical alarm (Red flashing LED + audible bleep)
Service warning (Yellow constant LED + audible bleep)
*Alarm levels are factory pre-set and may be varied according to industry best practice levels