Photoelectric smoke alarms: what you should know, and why they’re now mandatory

Posted on 18th March 2016 by excitemedia
smoke alarm installation

We all know that smoke alarms save lives: early detection of smoke or flames is the key to getting all of the occupants out of the building safely. Despite this, there have still been over 150 tragic deaths from house fires in Queensland over the last decade—which is why the government has now introduced legislation to mandate installing better smoke alarms in our homes. One of the recommendations is to make photoelectric smoke alarms mandatory. 

 

Recent developments in technology have also determined that some types of smoke alarms are better suited to domestic housing—and to eliminating Queenslandǯs house fire fatalities. A lot depends on where the alarms are located, on their power source, and on whether theyǯre connected in a system. The Government’s planned changes will be phased in over a decade, with regulations on the type of alarms that should be installed, and how they should be powered and hardwired.

If you’ve never heard of them, you soon will: photoelectric smoke detectors will be replacing most of the ionisation smoke detectors traditionally used in our homes, and it wonǯt be long before your home will be assessed for compliance with the new safety standards.

 

Photoelectric and ionisation smoke detectors

While ionisation alarms have been used extensively throughout Queensland homes in the past, theyǯre no longer the gold standard in smoke alarms, and they’ll eventually be phased out with the introduction of the Government’s new safety standards.

Ionisation alarms contain trace amounts of radioactive material that respond to the particles emitted in a fire. While they’re good at detecting fast-flaming fires, they fall short where there isn’t a lot of visible smoke—and house fires are characteristically dense with smoke.

Photoelectric smoke alarms (including dual sensor alarms, that contain both photoelectric and ionisation sensors) are now recommended by virtually all fire authorities, and are considered the best type for homes as they’re much faster at detecting smoke. They will usually respond to smoky fires within three to five minutes, compared with the response time of 20 minutes or longer for ionisation alarms—which means they will alert the occupants earlier, and give them significantly more time to escape the property in the event of a fire.

The difference between types of smoke alarms and how they’re powered and wired into the home can literally be the difference between life and death. While ionisation alarms can deliver an additional level of fire protection to a home, they’re no longer the best protection against fire fatalities, and Queensland families should consider upgrading their alarms as soon as possible.

 

How photoelectric smoke alarms work

Photoelectric smoke alarms are better at detecting a wider range of fire types, as well as sensing thick smoke and smouldering fires, than ionisation alarms alone. Photoelectric smoke alarms contain an LED light that acts like a laser beam, and a sensor, positioned perpendicular to each other.

When the smoke enters the chamber, the particles scatter the beam of light, activating the sensor, and triggering the alarm. Where an ionisation smoke alarm essentially feel the smoke, photoelectric alarms see it. Traditional ionisation detectors are sensitive to fast heat changes that flaming fires emit, but because of this they’re also known for alarming over burnt toast and steam from cooking.

Photoelectric alarms are better at detecting the smoke from smouldering fires—the sort of smoke that could come from cigarettes, or the dense smoke from burning soft furnishings—which is typical in a house fire.

Research in smoke alarm technology (and unfortunately, coroner’s inquests into deaths by house fires) has repeatedly revealed that traditional ionisation alarms will actually trigger when there’s a fire. The problem is that by the time they do, it’s often too late for the occupants to escape.

Rigorous testing and development in photoelectric technology, by contrast, has consistently demonstrated that photoelectric smoke alarms—or combination alarms that use both ionisation and photoelectric components—are faster and safer, especially for domestic use, and the Government has based its reforms on this evidence.

 

Mandating smoke detectors in Queensland

Too many people have died in Queensland from house fires over the last decade. Tragic events in the last few years were so devastating that the Government’s planned changes into mandating the installation of higher-quality smoke alarms has been largely uncontested, with most fire services and communities supporting the measures.

Over the next ten years, it’ll be mandatory for all domestic housing in Queensland to have smoke alarms installed that are photoelectric, hard-wired, or powered by a lithium battery with a lifespan of 10 years or more.

They’ll need to be installed in bedrooms, living areas, and escape paths. Itǯs also predicted that within 5 years, most Government-owned housing will be equipped with smoke alarms that meet the new safety standards.

While these measures are likely to spur innovation and cost savings over the next few years for better smoke alarm systems, thereǯs no reason that Queenslanders should wait to upgrade or replace their existing alarms.

New buildings and properties that have had extensive renovations will already have to comply with the new standards as early as 2017, with all houses sold or rented following in the few years after that—which is a large portion of Queensland’s current housing situation.

Photoelectric smoke alarms significantly reduce the risk of death in a house fire, and for Queenslanders concerned with the safety of their families, the cost of a new alarm system is a small price to pay. The main issue is having the new system installed correctly, which should always be done by a professional electrician with the right expertise.

Contact Dawson Electric for more advice on photoelectric smoke alarms and complete fire safety systems, and we’ll be happy to bring your home to compliance with the highest standards—and to protect the safety of you and your family.

Read more here about smoke alarm legislation