720r Addendum: Siting the 720r UK 1
Cooper Security Limited 2013 Every effort has been made to ensure that the contents of this leaflet are correct. However, neither the authors nor Cooper Security Limited accept any liability for loss or damage caused or alleged to be caused directly or indirectly by this leaflet. The contents of this leaflet are subject to change without notice. Printed and published in the U.K. Part No. 12357439 2
INTRODUCTION Cooper Security s 720r smoke detector provides detection of smoke or potential fire. It is however important to note that the 720r is not designed to be compliant with the EN54 or other local statutory standards covering fire alarm systems that automatically contact the fire services. As an installer you should not program an intruder alarm system using a 720r detector and associated system so that it is configured to replace systems that must meet EN54 or other local statutory standards. The 720r smoke detector is designed for use in family houses/apartments or small offices rather than commercial or industrial environments. The main role of the 720r is to detect smoke and provide a local alarm notification. Our smoke detector also sends a notification to the intruder alarm system. The alarm system control unit can then sound an alarm to notify the building s occupants or notify personnel remotely (for example a landlord or caretaker) using any communication device that may be fitted. The rest of this bulletin contains simple instructions on the approach that should be used to ensure the positioning of the 720r smoke detector is optimised. UK 3
FACTORS AFFECTING PERFORMANCE The 720r smoke detector is designed to do three things: Detect smoke. Sound an alarm when it detects smoke. Send a radio message to the alarm system control unit when it detects smoke. Each of these functions can be affected by the environment around the detector. Detecting Smoke The 720r is an optical smoke detector. This is one of the most common types of smoke detector in use. An optical smoke detector works by admitting a continuous flow of air to a small chamber that is shielded from all external light. Inside the chamber a lamp shines a beam of light through the air. A light detector (photocell) to one side of the beam looks for any light scattered by particles within the beam. The light is designed to be scattered easily by small amounts of smoke entering the chamber. All optical smoke detectors that operate in this way have the following challenges: They do not detect radiant heat. They do not detect heated air. Other types of particle can mimic smoke (for example dust, water droplets, insects or steam). The detector cannot detect any smoke if air movement around the detector is restricted. The advantages of optical smoke detectors are that they are robust and reliable, and do not need large expensive batteries. 4
AUDIBLE ALARM SOUNDER The 720r uses a piezo electric sounder that produces at least 85dB(A) of sound 3m away from the detector. The volume of the alarm sound can be reduced by distance, closed doors, heavy drapes or positioning the detector behind furniture or other items. Radio Signalling The 720r transmits radio signals on 868.6625 MHz, the standard frequency in the UK for alarm signalling. The alarm signals generated by the 720r are designed for Cooper Security control units and receivers. Radio signals from the 720r can be absorbed and/or reflected by metal structures, wire mesh, heat retaining window films, cabling, metallic pipework and other any other metallic items. For a detailed explanation of the factors affecting radio transmission please read Guidance Notes for Wireless Alarm System Installations, available to touchpoint members at www.coopersecurity.co.uk under the Support - Installation Assistance for Wireless Systems tab. You must position the detector in a suitable place that does not absorb its signals, or contains other transmitters that can interfere with those signals. WHERE TO PLACE THE DETECTOR All the factors described above mean that there are good places to site the detector to ensure that it will detect smoke reliably, give a clearly audible alarm, and provide a strong enough signal for any receiver. All these considerations come into play in the following recommendations: UK 5
To ensure that the detector can pick up any smoke: Place detectors high up, in spaces where smoke accumulates. On flat ceilings place the detector close to the middle of the ceiling. On pitched ceilings place the detector on the slope of the ceiling, at least one metre from the top. If you cannot place a detector on a ceiling, then mount one as high as possible on a wall, but at least 100mm away from the ceiling. Place detectors at the top of stair wells. To ensure that people can hear the audible alarm: Place a detector on the landing outside bedrooms. The sound level of the alarm inside the bedrooms must be enough to wake a sleeper. Place at least one detector on every floor of the house. To ensure that receivers can pick up radio signals from the 720r: Place detectors high up. Place detectors clear of any metalwork. Place detectors clear of any other radio transmitter. Read Guidance Notes for Wireless Alarm System Installations carefully for more detailed information. 6
WHERE NOT TO PLACE THE DETECTOR Do not place the detector in areas that smoke reaches slowly: Avoid dead spaces. Dead spaces include the angle between wall and ceiling: CEILING 100mm UK Centre of ceiling Never here 100mm min 150mm max Best location Acceptable location WALL 7
Avoid the angle at the top of a pitched ceiling: 900mm Horizontal distance from peak. Avoid closed rooms or cupboards if you are only fitting one or a few detectors. If you are going to fit several detectors then put one in each room where the door is normally closed. Avoid spaces where there is a lot of dust. Dust may accumulate on and within the detector, and prevent smoke reaching the sensor. Avoid the fresh air stream from ventilators or air conditioners. The flow of air will blow any smoke away from the detector. 8
Do not place the detector in areas where there may be cause for a false alarm. Avoid: Spaces where there is smoke, or similar, as part of everyday life: for example kitchens or garages. Central heating boilers, fireplaces, stoves, cookers, ash trays, toasters. Rooms with lots of water vapour/steam, for example bathrooms or washing areas, especially where this may cause condensation on or within the detector. Spaces where there may be many small insects, for example loft spaces or greenhouses. Spaces where there is a lot of dust. Dust in the air may trigger the smoke detector. Air contaminated by solvents, for example thinners, petrol or white spirit. Outside areas. Smoke and contaminants can arrive from any distance if the detector is outside of a building. EXAMPLES The diagrams on the next two pages summarise some of the good and bad positions for a smoke detector. The first diagram shows a single floor apartment. The second and thirddiagrams show a small three bedroom- two storey house. UK 9
Appartment Bedroom 1 Store Bedroom 2 Living room Hallway Bedroom 3 Bathroom Toilet Boiler Kitchen Hallway Balcony Bad position Good position 10
Kitchen House: ground floor UK Dining room Hall/Stairwell Bad position Good position Living room 11
Bathroom Cupboard Bedroom 1 Landing Bedroom 3 Bedroom 2 House: first floor 12
WHAT THE 720R CANNOT DO The 720r is designed for use in a small family home or apartment, or small office. It has the following limitations that are shared by many optical smoke detectors: The smoke detector cannot detect a fire if smoke cannot reach the sensor. Smoke from fire inside walls or attics, on top of roofs, or in other floors may not reach a detector quickly enough to cause an alarm in time for the occupants to escape unharmed. In addition, if the detector is deliberately covered to prevent smoke reaching it then it cannot detect smoke. The alarm sounder may not be heard. If an occupant is in another room to the detector, is hard of hearing, is asleep, or under the influence of drugs or alcohol, then he or she may not hear the alarm and be able to react to it. The detector may not be able to warn about smoke from fires caused by carelessness and general safety hazards, such as: smoking in bed, violent explosions, escaping gas, improper storage of flammable materials, overloaded electrical circuits, children playing with matches or arson. No smoke detector can detect every kind of fire. In particular, smoke from slow smouldering fires rises slowly and may not reach the detector until flame breaks out. UK 13
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Product Support (UK) Tel: +44 (0)1594 541 978 Available between: 08:30 and 17:00 Monday Friday, Product Support Fax: (01594) 545401 16