Water is a great conductor of electricity, which can be very dangerous in places like the kitchen, the bathroom or the laundry. There are certain rules and regulations in Australia that govern how switches and outlets can be placed in relation to water outlets and fixtures. Knowing them will help you to decide where the safest places to put your general power outlets (GPOs) are when you begin planning the layout of your bathroom or your kitchen. If you have any doubt about where things should go, consult a licensed electrician - they will know these rules all too well, and MUST be employed to do any electrical work.
For the purpose of wiring regulations, bathrooms are divided into four zones, in accordance with the Australian/New Zealand Wiring Rules (AS/NZS 3000:2007). These are as follows:
Zone 0 - This covers interior area of the base of the bath or shower.
Zone 1 - This zone is divided into three sections, depending on what you have installed:
- Bath - For a bathtub, Zone 1 is the vertical area from the inner rim of the bath to the ceiling, or 2.5m above the rim, whichever is lower (this usually encompasses zone 0 too).
- Shower over a bath - The area with a horizontal radius of 1.2m from the fixed plumbing connection of the shower (i.e. 1.2m out from the shower outlet).
- Shower - The area with a horizontal radius of 1.2m from the fixed plumbing connection of the shower. The vertical boundaries of this area extend from the floor to the ceiling, or up to 2.5m above the floor, whichever is lower.
Zone 2 - This is the area with a horizontal radius of 0.6m out from Zone 1, and a height of 2.25m above the floor (or to the ceiling, whichever is lower).
Zone 3 - This is the area with a horizontal radius of 2.4m out from Zone 2. The vertical boundaries of this area extend from floor to ceiling or up to 2.5m above the floor, whichever is lower.
- If you have a hand held shower in your bathroom that has a barrier (like a door or a shower curtain), a good tip to test electrical safety is to test the distance of the water spray when the barrier is in place. If it can reach a power outlet or a switch, then the switch or power outlet probably needs to be relocated.
Zone wiring regulations (sockets)
Where you can place sockets and switches in a bathroom depends on the zone:
- Zone 0 - No sockets are permitted.
- Zone 1 - No sockets are permitted.
- Zone 2 - No sockets are permitted unless they're incorporated into a shaver supply unit OR are protected by Residual Current Detectors (RCD) with a fixed rating of not more than 30mA, and in a cupboard (e.g. a vanity cabinet) that maintains the enclosure of the socket outlet during normal operation of the connected equipment.
- Zone 3 - Sockets are permitted provided that they're installed at more than 0.3m above the bathroom floor, and fitted with RCD protection.
Zone wiring regulations (switches)
- Zone 0 - No switches are permitted.
- Zone 1 - No switches are permitted unless they're installed higher than 0.3m above the bathroom floor with IPX4 specification.
- Zone 2 - No switches are permitted unless they're installed higher than 0.3m above the bathroom floor with IPX4 specification.
- Zone 3 - No switches are permitted unless they're installed higher than 0.3m above the bathroom floor. No specific IP rating is required.
Light fittings with an IPX4 specification are only permitted in Zones 1 and 2, while those in Zone 3 don't require a specific IP rating.
Kitchen and laundry zones
Slightly different rules apply in other areas of the house like kitchens and laundries around sinks, basins or other fixed water containers. The distance that electrical outlets (GPOs) can be from a sink is determined by how much water it can contain. Sinks, basins or other fixed water containers that hold less than 45 litres have slightly different rules than those which hold more.
For fixed water containers anywhere outside of the bathroom, there are two zones defined:
Zone 0: The area inside the sink or basin, in which nothing is allowed to be installed.
Zone 2: Determined by whether or not the container holds more than or less than 45L - no fittings are allowed inside zone 2.
For containers that hold less than 45L, zone 2 is defined as 0.4m above the top of the container, and 0.15m from the edges of the water container. For those that hold more than 45L, it's 1.0m above and 0.5 metres from any given side.
Note that these rules only apply for GPOs - other 'switches and accessories' aren't allowed within 300mm of a fixed water container at all, and must be IPX4 rated if they're to be installed at a distance greater than or equal to 300mm from the fixed water container inside zone 2. Consult your electrician for exact details.
You can never be too careful where something as volatile as electricity is concerned, especially in a high-risk area like the bathroom. Safety switches monitor the flow of electricity through a circuit and automatically cut the power supply if current is detected leaking from faulty switches or wiring. While they are not a complete guarantee against electrical shocks, they do work to minimise the damage done, and could make all the difference.
Since 1992, all new houses in Australia are required by law to have safety switches installed. There are three types of safety switches available:
- Switchboard mounted safety switches - These are the most basic of safety switches and monitor the fixed wiring and electrical appliances in your household. It is mandatory by law for every home to have these installed by a qualified electrician.
- Safety switches in place of regular power points - These switches replace your standard GPOs and protect any appliances that are plugged into them. They also need to be installed by a qualified electrician.
- Portable safety switches - These can be used both indoors and outdoors, and are essential to use if you are using electrical appliances that are not protected by one of the safety switches listed above.
A final caveat: All electrical work in Australia MUST be done by a licensed electrical contractor, who should properly test any electrical work and supply you with a safety certificate.