Many of us have had our arm hanging out the car window, moving our hand up and down in the wind as we drive along.
Yet some people may not realise you are breaking the law by doing so, even as a passenger.
All states across Australia prohibit motorists and passengers from placing limbs out of windows and the offence can come with a hefty fine.
In NSW, drivers can cop a fine of $337 as well as an additional three demerit points, while passengers can receive the same financial punishment.
“A person must not travel in or on a motor vehicle, with any part of the person’s body outside a window or door of the vehicle,” NSW legislation reads.
This means acts such as sticking your hand out the window and waving at friends is breaking the law.
In Queensland, drivers and passengers face a potential fine of $298, while Victorians can find themselves $141 out of pocket.
South Australians will be made to pay $244 and surrender three demerit points if found guilty of the offence, while WA residents face a fine of $50 and one demerit point additionally for drivers.
The only exemption to the road rule is if the driver is signalling with their arm to either turn right or slow down and stop.
NRMA Road Safety Expert Dimitra Vlahomitros told Yahoo News there is “simply no reason” for drivers or passengers to have their arms outside of vehicles’ windows or doors while in motion.
“Drivers and passengers need to apply common sense – it’s not only illegal but downright dangerous, and that’s because you could risk losing a limb,” she said.
“We know that kids mimic our behaviour, which is why it’s so important to make sure we’re modelling the right road safety behaviours.”
The obscure law is one of many little-known road rules which have come to light in recent weeks.
One NSW motorist was fined $448 and received three demerit points after having a dirty registration plate.
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