Smoke Alarms
While smoke alarms may all look very similar, there may be quite different in the way they work.
There are essentially two types of Smoke Alarms, Photo electric and Ionisation, and both are designed to detect fires differently to each other. They operate at either end of the spectrum of fire detection.
Additionally, there are special alarms for specials needs, such as for the hearing impaired or for particular parts of buildings
Photo-electric Smoke Alarms
Photo-electric smoke alarms 'see' smoke.
They detect visible particles of combustion, eg. smoldering cigarette smoke. They respond to a wide range of fires, but they are particularly responsive to smoldering fires and the dense smoke given off by foam filled furnishings or overheated PVC wiring.
Advantages:
- Good for smoldering fire and dense smoke
- Not as prone to cooking nuisance alarms as ionisation alarms
- Contain no radioactive material
- Suitable for general use
Disadvantages:
- Slightly more expensive than ionisation alarms
- Nuisance alarms can occasionally occur from dust and insects
- They must be kept clean
Ionisation Smoke Alarms
Ionisation smoke alarms 'feel' smoke.
They detect invisible particles of combustion, eg. from cooking toast. They activate more quickly for fast, flaming fires with little visible smoke.
Advantages:
- Slightly cheaper than other types of smoke alarms
- Very good with fast flaming fires with little visible smoke
- Less prone to false alarms caused by dust and steam
- Suitable for general use
Disadvantages:
- Can be susceptible to nuisance alarms if placed too close to cooking
- May be slow to respond to slow smoldering fires
- Contain a very small amount of radioactive material
Alarms for the Hearing Impaired
Conventional smoke alarms are not effective in alerting those with hearing impairments. A visual warning device which can be interconnected to the smoke or heat alarm can be obtained.
Some models include an intense flashing strobe light in the control panel, along with a vibration pad which can be placed under the pillow and which will arouse the sleeping occupant in an emergency. The control panel will often have an ancillary socket for attaching an additional strobe light (e.g. to give an alarm downstairs during the day) or an extra vibration pad.
People who wish to purchase smoke alarms for the Hearing Impaired should contact the relevant association in their state for information on where they can be sourced.
Relevant Associations
Deafness Resources Australia
Phone: 1800 555 201
TTY: 1800 555 203
Fax: (02) 9895 2972
Deafness Resources Australia website
Deafness Forum of Australia
218 Northbourne Ave
Braddon ACT 2612
(02) 6262 7808
Deafness Forum of Australia website
Self Help for Hard of Hearing People (SHHH)
1334 Pacific Highway
Turramurra NSW 2074
(02) 9144 7586
Self Help for Hard of Hearing People (SHHH) website
Better Hearing Australia
(Sydney Branch)
29 Burwood Road
Concord NSW 2137
(02) 9744 0167
Better Hearing Australia website
Deaf Society of NSW
PO Box 1060
Parramatta, NSW 2124
Phone: (02) 9893 8555
Fax: (02) 9893 8333
TTY: (02) 9893 8858
Deaf Society of NSW Website
Australian Association of the Deaf
(Sydney office)
PO Box 4681
North Rocks NSW 2151
(02) 9871 8400
