For decades, smoke alarms have been a staple of Queensland homes, and for good reason – those living in houses without a functioning smoke alarm are more than 3 times as likely to be involved in a fatal house fire. With this fact, you’ll understand it’s critically important that your smoke alarm is properly installed and maintained.
9 volt or 240 volt
All homes built since 1st July 1997 have been fitted with 240v smoke alarms, as required by legislation. Houses older than this are likely operating on 9v retrofitted smoke alarms. The advantage of the 240v smoke alarm is increased reliability and convenience; the smoke alarm is still fitted with a 9v battery, however this is only as a back-up, with the unit being powered primarily by the 240v mains. The result is far fewer battery changes (and fewer intermittent beeps in the night).
Ionisation or Photoelectric
There are two leading technologies in household fire detection: ionisation and photoelectric. Each offer unique advantages.
Ionisation is found to be more responsive to active, flaming fires. In addition to this, the initial unit price is generally around half the price of the photoelectric.
Photoelectric is more responsive to slow-burning, smouldering fires. For this reason the Queensland Government recommends the use of a photoelectric smoke alarm over ionisation.
Smoke alarms should be positioned on ceilings, as far from corners as possible. The smoke alarm must be installed in a hallway near bedrooms. Multi-storey houses must have a smoke alarm on each floor; levels without bedrooms should have a smoke alarm near the stairwell.
Areas with excessive air movement (near air conditioners, windows, or fans) should be avoided, as air currents may prevent smoke from reaching the detector. Ideally the smoke alarm would be kept away from kitchens and bathrooms, as steam and smoke may set off false alarms.
It’s important to perform regular tests on your smoke alarms – although they have failsafe measures built in, like any electronic device they can fail suddenly and silently. Try to remember to press the ‘Test’ button at least once a month on each of your smoke alarms.
Remember to replace the batteries every year, and avoid painting the unit. False alarms do happen, but try to avoid taking out the batteries, instead use a fan or open a window. Once batteries are taken out they are often forgotten.
Additionally, it’s important to remember that smoke alarms have a service life of just 10 years. Any units older than this should be replaced.
If you would like your smoke alarms replaced or upgraded, contact a licensed electrician. And since you’re already here…
Changing a light bulb – it’s the classic example of a simple task, but a well designed lighting system actually has a lot of thought put into it. The positioning, brightness, and colour of your lights can have great effects on your mood and productivity throughout the day.
For existing home owners who are not looking to add new light fittings to their house, there is a great deal of variation in available power outputs and colours, which has been further complicated by the advent of modern lighting technologies.
Traditionally, all home lighting has been provided by incandescent lights, the age-old technology brought to commercial production by Thomas Edison in 1878. While many refinements have been made since then, it has only been in recent years that compact fluorescent and LED lamps have become suitable for use in the home.
So what should you be looking for in a light?
It’s easy to consider the wattage of a light the determining factor in a light’s brightness, and while there is a strong correlation, the method falls short when considering compact fluorescent and LED lamps.
The unit used to measure the light which hits a surface is called the lumen. A comfortable brightness to aim for in the home is 150 lumens. So if, for example, you have a 10 square-metre room with 2 lights, you should look to buy two 750 lumen lamps (150 x 10 / 2).
As with the colour temperature, the brightness also should vary depending on the room’s purpose. While 150 lumens is comfortable for bedrooms and living rooms, kitchens and offices may benefit from 250-500 lumens.
The best solution to ensure an ideal brightness is to install a sufficiently powerful light in combination with a light dimmer. A dimmer allows you to adjust the brightness of your lights by use of a dial located with your light switch.
Everyone is no doubt familiar with the standard 60W incandescent light bulb. The 800 lumen output of one of these light bulbs is matched by the compact fluorescent with a 14W power consumption, and the modern LED with only 7W. To put it simply: LED > Compact Fluorescent > Incandescent.
When considering energy consumption, you should also consider the initial cost of the light. Although LED has the best energy efficiency, it is also the most expensive of the current options. This has been continually falling as the technology becomes more popular, but at the present they are still not necessarily the best value light.
It’s clear that the LED will be the the future leader of home lighting for at least the next decade or two. If you’re holding out for a price drop, the compact fluorescent will treat you well enough.
Electricity. A pretty great thing, no doubt, but it’s not without its dangers. An overloaded circuit or misdirected current has the potential to cause explosions, fires, and electrocution.
Engineers around 150 years ago found a way to reduce the risk of the first two of these bad things. It’s called a Fuse – essentially a thin section of wire designed to be the weak point in an electrical circuit. When a circuit’s current reaches a dangerous level, the fuse disintegrates and the path is broken. The fuse design has been updated endlessly over the past century, and has now largely been replaced by the Circuit Breaker, which offers similar features with the added benefits of being reusable.
These devices, however, rarely prevent electrocution – that is, death by electric shock. There are two common forms of electrocution:
- Fibrillation of the heart. Currents as low as 30mA (milliamps – 1 thousandth of an amp) may cause the heart to lose its ‘rhythm’ (arrhythmia) and result in cardiac arrest if not treated with a defibrillator.
- Burn or cell damage. Larger currents (over 1 amp) flowing through the body cause extreme heat, which is not something internal organs enjoy.
This is where the RCD (residual current device, also known as a Safety Switch) comes to save the day. By comparing incoming and outgoing current at the electrical switch board, the RCD can detect whether any current has been redirected through a second path – such as through a human body connected to ‘earth’ (I’ll explain this concept in a later blog post). The RCD will trip when a current differential of 30mA or more is detected, thus isolating the supply and hopefully saving the life of the involved person.
RCDs are now an established technology, with most ‘first world’ countries adopting the devices into their Wiring Standards.
Recent updates to the Australian Standards have necessitated the installation of RCDs to all new or modified power and lighting circuits in domestic buildings rated up to 20 amps, which includes nearly all household circuits.
If you would like to protect the members of your household by installing RCD protection, please get in touch. We would love to help!