In order to prevent the spreading of fire, smoke and heat and to keep fires contained, internal fire doors are designed to be closed at all times. This is why when you open a fire door it closes behind you (courtesy of the door closer) to maintain its closed position. However in high traffic areas within a building it is not uncommon to see doors propped open (often with fire extinguishers or wedges) which is, of course, not keeping the door in its advised position for fire safety and therefore posing a risk to personnel.
In such areas it is understandable that needing to open the door and having it close every time someone goes through can be annoying so manufacturers have come up with devices that can be fitted to fire doors which do not conflict with the requirements of use of the doors.
DoorSense from Union, part of Assa Abloy Security Solutions (a UK division of Assa Abloy) is a legal way for fire doors to be kept open for access and be able to close automatically in the event of an alarm.
The system is CE marked to EN 1155 standards, meeting legal requirements to allow fire doors to be kept open, assisting access and providing greater movement in a building when needed, while reacting fast should a fire occur.
DoorSense is a battery operated standalone system, activated by simply opening a fire door pushing the system’s foot plunger down into the floorplate, holding the door open to ease access into the building. When a fire alarm sounds, the unit uses acoustic technology to identify the alarm and automatically release the foot plunger, allowing the fire door to firmly close via a separate door closer.
A DoorSense system can be retrofitted to doors using older holding mechanisms, will work at any angle, and can be released manually or automatically via the alarm or by using a built-in night closing timer.
According to Assa Abloy, the acoustic technology within DoorSense has been tested over 50,000 cycles to guarantee it will work – in addition to EN1155 and any other tests that door release mechanisms are subjected to.
DoorSense can be specified in three colours – black, white or red – and is powered by two alkaline C batteries, which are included as part of the overall package.
Read the full product review in the November 2017 edition of PSI magazine
