Table B shows how the built in microprocessor reacts to differ-
ent levels of CO gas and exposure time. At higher levels of CO
the alarm turns on sooner. The rate of flashing of the red light in-
dicates the level of CO.
If your CO Alarm sounds, follow the instructions given at
the top of page 2.
When ventilation is provided by leaving the windows and doors
open, the CO build up may have dissipated by the time help ar-
rives and the alarm will have stopped sounding. Although your
problem may appear temporarily solved, it is crucial that the
source of the CO is determined and appropriate repairs made.
NEVER IGNORE THE ALARM.
Pre-Alarm:
When the alarm detects over 50ppm CO the red
light flashes every 5 seconds. This helps locate CO leaks as the
unit gives an indication straight away. (Without this feature the
CO level would need to be at 150ppm CO for up to 30 minutes
for an indication to be given). Note the Pre-Alarm signal may be
triggered by CO coming for example, from cooking with gas,
from car engines or from nearby barbecues. This is usually not a
concern unless the Pre-Alarm signal persists for over an hour
and the CO source is unknown.
NOTE:
The CO Alarm may sound if cigarette smoke is blown
into it or aerosols are released nearby.
CO Alarm Memory:
This tells you if the unit has detected CO in your absence and
helps to detect and locate leaks, monitor premises etc.
When the test button is pressed the horn sounds and the indica-
tor lights flash as follows:-
-
Red Light
is Off if no CO is detected since reset or power-up.
-
Slow Flashing Red Light
(every 2 seconds) if 150ppm CO
has been detected since power-up.
-
Fast Flashing Red Light
(every ½ second) if 350ppm CO has
been detected since power-up.
Reset Memory
by holding down the test button for over 20 sec-
onds until the red light stops flashing. Cover the horn with a cloth
to muffle the alarm.
3.1 Suitable Locations
Ei Electronics recommends that the advice of the
Health &
Safety Exectutive (HSE) UK
is followed as this is based on re-
search done at the BRE subsequent to the issuing of the BS
7860 : 1996 standard.
The Health & Safety Executive (HSE) UK
, give the following
recommendations for rooms where CO alarms should be lo-
cated - these are in order of priorty:
- In rooms with flueless or open flued appliances
- In rooms where the occupant spends most time
- In bedrooms
British Standard BS7860:1996 gives the following advice:
Ideally you should have a detector in or near every room that
contains a fuel-burning appliance.
However, if you have more than one appliance, but only one de-
tector, you should take the following into consideration when de-
ciding where best to put the detector.
(1) If there is an appliance in the room where you sleep, you
should put the detector in that room.
(2) If there is an appliance in a room that you use a lot, e.g. a sit-
ting room, you should put it in that room.
(3) If you live in a bedsit, put the detector as far away from the
cooking appliances as possible, but near to the place where you
sleep.
(4) If the appliance is in a room not normally used (e.g. a boiler
room), put the detector just outside the room so that you will be
able to hear the alarm more easily.
Ideally you should have a detector in or near every room that
contains a fuel-burning appliance.
3.2 Unsuitable Locations
Do not place the CO Alarm in any of the following areas.
(1) Within 1.85 metres (6 feet) of the appliance.
(2) Outside the building.
(3) In or below a cupboard.
(4) In a damp or humid area.
(5) Directly above a sink or cooker.
(6) Next to a door or window or anywhere that it would be
affected by draughts.
(7) Where it would be obstructed by curtains or furniture.
(8) In an area where the temperature could drop below -5
°
C or
rise above 40
°
C.
(9) Where dirt or dust could block the sensor and stop it work-
ing.
(10) Where it could be easily knocked or damaged, or where it
could be accidently turned off or removed.
(11) In sockets where the power is likely to be turned off.
(12) In a bathroom or where the CO alarm may be exposed to
water splashes or condensation (e.g. above an electric kettle).
(13) Near paint, thinners, solvent fumes or air fresheners.
(14) Plugged into extension sockets.
3.3 Installation
The
HSE (
UK), gives more detailed recommendations as fol-
lows:
If locating the CO Alarm in a room with an appliance:
- the alarm should be located between 1m and 3m horizontally
from the appliance. (To comply with both BS & HSE advice lo-
cate between 1.85 and 3.0m from appliance).
- the alarm should be located preferably on the ceiling. Ceiling
mounted detectors should be at least 300mm from any wall.
- if placed on a wall the CO Alarm should be as high as possible
(higher than doors and windows) but not within 150mm of the
ceiling.
If locating the CO Alarm in a room remote from the appli-
ance:
- the alarm should be located at a level similar to the breathing
zone of the occupant (typically in the living rooms at 1.5 to 2.0m
above floor level and in bedrooms at the height of the bed).
7
5
Where to place CO Alarms
3.
6
Figure 1
Bedroom
*
Kitchen
*
Sitting
Room
*
*
If they contain or are near a fuel-burning appliance
