How to Choose a Smoke Detector: The Ultimate Guide

house on fire for smoke alarm installation in sydney

There are a range of smoke detectors available, and the laws and fitting process of smoke detectors can be confusing. This guide includes a comprehensive overview of smoke detectors, complete with up to date smoke alarm information. Given that the majority of house fires occur during the night, and that sense of smell is absent during sleep, fire safety is extremely important. In addition to the threat of the fire itself, toxic fumes can overcome a sleeping person. A smoke detector can significantly increase chances of preventing or surviving a house fire.

What is a smoke alarm?

A smoke alarm detects smoke, usually in indication of a fire – this can be in a residential or commercial setting. Smoke alarms may come in various different forms, with each aiming to ensure that house fires can be escaped quickly and safely. In Australia, there are strict laws and regulations regarding the placement and maintenance of smoke alarms.

Smoke detectors in commercial settings are often powered by a central fire alarm system, whereas residential devices can range from individual battery powered devices, to several linked mains powered units (with battery backup).

smoke alarm example

Although the terms smoke alarm and smoke detector are colloquially interchanged, they are technically different devices. Smoke alarms include both a smoke sensor and sounding alarm, whereas a smoke detector usually will contain only a smoke sensor. However, this article will assume that the terms are interchangeable, and will refer to systems with both smoke detection and audible alarms (as these are the common choice within residential settings).

How do smoke detectors work?

The way a smoke detector functions will depend on the type of system in place. There are two main types of smoke sensors; these are photoelectric smoke alarms, and ionisation alarms (further features are explained in the following section).

Photoelectric smoke alarms are superior when it comes to sensing smouldering fires; slow burning fires, with less significant flames (these are common as house fires). This type of device detects smoke optically, and research has shown that photoelectric units are more effective than ionisation smoke alarms.

Ionisation smoke alarms, on the other hand, are effective in detecting fast burning fires with significant flames. They contain a small amount of radioactive material, which can react to particles emitted within a fire. These fire alarms are not as effective when detecting fires that are smoky and smouldering.

Additionally, smoke alarms are available that include both sensor types; these can be a good option depending on placement.

Other smoke alarm features

Aside from the two main types of smoke detectors, smoke alarms can have varying features and will be suitable for differing situations.

  • Battery powered home smoke alarms may be installed when it is not possible to connect a mains-powered smoke alarm. Many regulations in Australia prevent this type of smoke alarm from being installed in new dwellings and buildings.
  • Mains-powered home smoke alarms are permanently connected to the power supply of a home and have a back-up battery which is useful in the event of a power outage. This type of smoke alarm must be installed by a licensed electrician.
  • Wireless smoke detectors have interconnectivity features, allowing each alarm to be connected to each other. Therefore, if one alarm is set off, this activates all other alarms in the home.
  • Heat alarms can detect heat instead of smoke; they can be useful in settings such as kitchens, as they will not accidentally be set of by smoke during cooking. They are also popular in laundries and roof cavities.
  • Carbon monoxide alarms are used to ensure the safe operation of central heating systems, as carbon monoxide is a product of gas heating. If a heater develops a fault, carbon monoxide can spread through a home at dangerous levels.
  • Other features may include a hush button, an escape light, or a test button.

How to get fire alarms fitted

When getting fire alarms fitted, there are a few guidelines you should follow. Firstly, if your smoke detector is hard wired, it must be installed by a licensed electrician. Furthermore, you should ensure that when installing smoke alarms, it is done in accordance with manufacturer instructions and relevant laws and regulations.

The ideal position for a smoke alarm is usually on the ceiling, between sleeping and living areas. Our smoke alarm installation service in Sydney can help find the right alarm for your needs.

Are smoke alarms mandatory?

When it comes to Australian rules and regulations regarding smoke detectors, there are various laws and restrictions. These differ depending on the state (and can change, so be sure to check the official relevant requirements when installing or replacing smoke alarms); some examples are listed below.

  • In NSW, there is a minimum requirement of one smoke alarm per level within a home. Furthermore, Fire and Rescue NSW research recommends “installing smoke alarms in all bedrooms and living spaces (including hallways and stairways) and even the garage (Fire & Rescue NSW Research, 2019). It has been over 10 years since smoke alarms became law across NSW.
  • In QLD, interconnected photoelectric alarms are required, and should be replaced after 10 years. These units can be mains-powered or otherwise must have a 10-year battery.
  • SA, WA: These states require at least one smoke alarm per home. Overall, photoelectric smoke detectors are recommended, and in most cases, devices should be mains-powered or contain a 10-year battery. Interconnection may also be required depending on the circumstances.

For a more up to date and in-depth overview, view government documents and resources in relation to your state.


Ultimately, smoke detectors are extremely important, as they significantly increase chances of survival during a house fire. In addition to smoke alarms, it may be a good idea to have a fire blanket, fire extinguisher, and escape plan ready, depending on the situation and setting. Fire alarms can come at various price points, from numerous brands. Be sure to test your smoke alarms regularly.

When it comes to the installation of smoke alarms, Action Electricians are fully licensed electricians; get in touch to find out what smoke alarm system can work best for you.

Jim Beasley