As the Dorgard is an audio sensing device that can be adjusted within certain limits, it is not necessary to carry out a test before the installation. If the Dorgard cannot “hear” the alarm to respond to it the likelihood is that the alarm is not sounding at the minimum level required by BS5839 which should alert the user to a problem with the alarm system that will require remedial action. The Dorgard should be removed until the alarm has been rectified to meet the minimum sound level required by the British Standard. When equipped with a Dorgard, fire doors can be held open at any angle by simply pressing the plunger down with your foot, and nudging the top of the plunger is all that’s required to release the door manually. In the event of a fire the Dorgard will release automatically when the fire alarm system activates by retracting the plunger which passes through the main body – the standard model listens for a sound level of over 65 dB while the Pro model is wired directly into the building’s alarm system.

BSI, the business standards company has revised BS 7273-4:2015 Code of Practice for the operation of fire protection measures – Part 4: Actuation of release mechanisms for doors. The new document has been developed with the FIA and other bodies. Employees should be informed about Dorgard and instructed on its use and operation and include it in the workplace fire routine.Previously, a device local to the doors effectively switched the doors to fail safe mode and released electrically secured fire exits and closed fire doors held open on magnetic door retainers. However, this is not always the case and a truly fail safe mode is not achieved. If the end user wants doors held open then his fire detection system needs to be up to scratch, it goes hand in hand and is not an "either or". The operation of the Dorgard, or the ability to hear the fire alarm, should not be affected provided the sound level stated in BS 5839 is adhered to throughout the building.

Text has been shortened and simplified to make the standard more straightforward to use. Some of the commentary has been moved to new informative annexes and some of the previous text has been tabulated. The Dorgard is a battery operated, acoustically activated fire door hold open device. The Dorgard performs its function by a rubber plunger/stopper that interacts with the floor directly or a designated floor plate to hold a fire door open. Easy-to-install in under 5 minutes, simply fix to your fire door with 4 screws and insert the batteries – no wiring or mains power required This compares with other similar retainers that are wired into the fire alarm system and have a built-in delay. Where an electrically powered hold-open device is fitted to a fire door between a corridor and a stairway, a Category L5 systemAnthony Burd, Head of the Construction Sector at BSI said: “Until the development of BS 7273-4 in 2007, there was no code of practice with recommendations governing the interface of fire doors and the fire detection /fire alarm system, although there was guidance for the devices themselves.” c) A smoke detector should be located on the ceiling of the adjacent landing within the stairway enclosure. During normal operation, the Dorgard continuously monitors all functions. If at any time it detects a possible fault or maintenance issue, it will revert to Fail to Safe in which the Dorgard will no longer operate as a hold open device. The device will also emit a series of beeps serving as a continuous warning. Staff should report any issues to the helpdesk at extension 2001 to arrange for maintenance. Dorgard only listens for a sound every 4 seconds and the sound has to be continuous for 10 seconds for it to operate. This helps to preserve the battery life of the unit and means the operation should not be delayed by any more than 14 seconds. I have asked fire officers why they have a policy against dorgards. The only arguments I have been given are these:

The Dorgard can hold a fire door open to maintain the functionality of the building by allowing an uninterrupted flow of people through the building during the day and releasing the fire door to close in the evening. You can also adjust the Dorgard to automatically close at night. To prevent warping Dorgard self-tests every seven days which helps to ensure the reliability and alleviate stress to the door which on doors that are wedged open for long periods of time, would cause warping. This self-testing also helps to prevent seizure of the overhead door closer by allowing it to cycle itself. We review the key role of a fire door retainer as part of your fire safety measures, and provide practical guidance about the 2015 Code of Practice for the operation of fire protection measures. Dorgard Fire Door Retainer Guidance A self-test routine is run every seven days by the Dorgard. The plunger is released, closing the door and the unit will emit a warning alarm if a fault is detected. When the batteries are running low, an audible warning will be sounded every 17 minutes in the form of a series of beeps and a red LED will flash to warn of the depleting batteries until they are fully exhausted, removed or replaced.

Hold Open & Free Swing

In the event that the batteries reach a low voltage or the battery compartment is tampered with or opened, the Dorgard fire door retainer will automatically release its plunger, closing the door, thus making the design fail-safe. The plunger can not be used to keep the door open if there are no batteries in the unit or the batteries have no voltage left. For the earliest detection of fire and sounding the alarm, it is better to have smoke detectors in adjacent rooms, as the Dorgard is triggered by the sound of the alarm. The guidance in BS 7273-4:2007, Annex A of the previous standard is now normative and, therefore, the standard includes recommendations (in tables in Annex B of this version) as to which category of actuation is appropriate for a particular application. In situations where the ambient noise level is above 80 dB, Dorgard has a safety feature that allows it to release automatically to all sounds above 65 dB as you would probably not hear a 65 dB fire alarm over the noise level in this situation. a) Smoke detectors should be provided in the section of corridor that forms the route to the stairway.

These door holders can be powered by batteries, from the mains, or from nearby power supply units (PSU) rated at 12V or 24V DC. It is generally recommended to install them at the top of the door to prevent warping caused by the door closer pulling against the electromagnet. Battery-powered versions typically use an acoustic sensor to listen for an alarm sounder while wired models will often be connected directly to the fire alarm panel. Dorgard’s react to a sound level adjustable between 65dB and 85dB, so all sounds in excess of 65dB will activate the Dorgard. This complies with BS5839 which gives 65dB as the minimum sound level for fire alarms. To prevent warping, Dorgard self-tests every seven days which helps to ensure reliability and alleviate stress to the door, which on doors that are wedged open for long periods of time, would cause warping. This self-testing also helps to prevent seizure of the overhead door closer by allowing it to cycle itself. Bedroom doors, another contencious issue. After all, what are we trying to do? We are trying to give people in residential care a homely atmosphere, some of them do not like their bedroom doors closed at night, and are distressed if they are. In my opinion, it is quite acceptable to use Dorgards on bedroom doors at night, providing their use is well managed. This means educating staff to realise exactly how they work, and that should the fire alarm sound, staff must proceed to the affected area and ensure that all bedroom doors are closed immediately (they probably will already be closed by the time they arrive!)Employees should be informed about Dorgard and instructed on its use and operation. It should also be included in the workplace fire routine. Fire doors are typically designed to be kept closed at all times so that fire and heat are contained and their spread minimised. This is achieved through use of well-engineered fire doors. However, on occasion they may be held open to facilitate convenience and/or accessibility around a building and in this situation mechanisms to hold them open, should follow BS 7273-4.