Manual

Dorgard must only be used for the purpose for which it is designed. Dorgard is
not suitable for external use. Read this Guide and follow the instructions
carefully, keeping it in a safe place e.g. in your Fire Risk Assessment file, for
future reference.
BS EN1155:1997 states that a door must not be retained at an open angle of less
than 65 degrees. It is recommended that the Floorplate be installed to comply to
this standard.
Dorgard, when installed correctly, complies with BS 7273-4 Category C.
Supplementary information about the sound of a fire alarm:
The British Standard for fire alarm installation, BS5839-1: 2002, (Clause 16.2), states: -
The sound pressure level of alarm signals should be generally, throughout all accessible
areas of the building not less than 65dB(A) . . . where the sound pressure level of background
noise is greater than 60dB(A), the sound pressure level of the fire alarm signal should be 5dB
above the sound pressure level of the background noise.
It is understood that there are some noises in everyday life that may be louder than a fire
alarm and persist for longer than 30 seconds, such as a vacuum cleaner. Although required
in the British Standard, it is often found that the alarm is not 5 decibels louder.
When Dorgard is holding a fire door open, it “listens” for the continuous sound of a fire
alarm. Dorgard needs to “hear” a fire alarm that exceeds 65 decibels for longer than 14
seconds. At a general noise level of 80 decibels Dorgard will release. This facility has been
built into the unit as a safety feature. Should the noise level in your premises exceed 80
decibels it is unlikely that you would hear a 65 decibel alarm, hence the Dorgard releases
the fire door to close.
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Important Information