Selecting and installing smoke alarms?
Smoke Alarm
The warning provided by smoke alarms has been responsible for saving thousands of lives and homes throughout the world. All of my properties have smoke alarm(s) installed and regularly tested.
So, how do they work?
There are two types of smoke alarms, these being ionisation and photo-electric, and each detect smoke differently.
Ionisation alarms use a small amount of radioactive material to ionise air in the sensing chamber. Under normal operation, the ionised air chamber becomes conductive. When smoke exists and enters into the chamber, the sensing chamber becomes less conductive and triggers the alarm.
Photo-electric smoke alarms use a light emitting diode and a light sensitive sensor in the sensing chamber. When smoke exists, the smoke particles block the light and trigger the alarm.
And which one should I use?
I did some research and according to the Fire and Emergency Services Authority (FESA) that photo-electric smoke alarms consistently provide sufficient time for occupants to escape from smouldering and flaming fires, provided the alarms are installed and maintained properly and the occupants hear them.
On a side note, if possible, use the smoke alarms that connect to the main 240V with a backup battery. It is also important to know that you need an electrician to install it for you, to make it easy, Australian Standard AS 3786 created with the specification of the smoke alarm so you are not buying a duck.
Interconnecting smoke alarms?
Some smoke alarms can be setup in a network where one smoke alarm is triggered, all other smoke alarms on the same network will also activate.
This can be very useful in larger homes where it may be difficult to hear smoke alarms that are at the other end of the house, or on another level. For example, garage downstairs and you are living upstairs.
Where should I install smoke alarms?
It is recommended that smoke alarms be located in all sleeping areas and in all of paths of travel between sleeping areas and exits to the open air. Having said that, smoke alarms should not be installed in close proximity to the kitchens, laundries and bathrooms because the appliances near by may trigger a fault positive.
I have seen many people pull the battery out because they are sick of fault positive, by doing that, you are risking your life in the event of fire. The best solution is relocation the smoke alarm.
Also, don’t install smoke alarms too close to any corner because of dead air space. A general rule is minimum 300mm to any corner. But for more specific detail, please check the Australian Standard as it may change from time to time.
Finally, smoke alarms maintenance
- Test once per month by holding the testing button for a couple of seconds, this ensures the battery and the alarm sounder are operating.
- Replace the batteries annually where appropriate. A good rule of thumb is Autumn every year as it’s starting to get cold. (Even you are on 240V, there is a backup battery in the unit need replacing)
- Cleaning with a vacuum cleaner annually to remove particles that will affect smoke alarm performance.
- You can also buy ‘smoke’ in a spray can to test your alarm. DO NOT START a real fire to test.
Special thanks to FESA at http://www.fesa.wa.gov.au for information.
PS: We are using smoke alarms PDL SD100 in most of our investment properties.
Drop me a note or comment and tell me what you think of smoke alarms?
We need smoke alarms in homes, offices and schools. It would not completely safe without alarms such as this because we will never know when potential danger happens. Others may think that installing alarms could be costly but we can never put a price tag on the feeling safety that this brings especially to our love ones.