Noise is a growing problem

Noise from heavy vehicle engine compression brakes is a significant and on-going cause of complaint for many NSW residents.

Engine brakes are devices fitted to the engine of heavy vehicles to slow the vehicle down. They are often referred to as ‘auxiliary braking devices’ or ‘secondary retarders’. A driver switches on the engine brake and it engages on release of the acceleration pedal. Engine brakes operate by causing the engine to act as a compressor when braking. The compressed air is released in short bursts which cause the characteristic engine brake ‘bark’. It is mostly the nature of this noise, rather than its volume that causes annoyance.

Engine brakes improve vehicle safety by reducing the load on service brakes on a steep descent but their use elsewhere provides little safety benefit. They can also extend the life of the vehicles service brakes and reduce maintenance costs. To date there has been no standards or regulations in existence around the world that are specifically targeted at the control of excessively noisy engine brakes to base Australian regulations on,

Trucking is an important business. But the constant use of noisy engine brakes is hurting the industry’s image. The RTA is working with the road transport industry to reduce the environmental impact of heavy vehicles on the community.

Complaints have increased from residents affected by heavy vehicle noise. The worst problems occur when drivers use their engine brakes unnecessarily near built up areas, especially at night when residents are trying to sleep.

Proposed regulations – engine brake noise

The RTA has worked closely with the National Transport Commission to develop an in-service standard for a regulatory response to the problem of engine brake noise. The Australian Transport Council unanimously approved the introduction of the engine brake noise standard in October 2007.

It is proposed to apply the standard using three types of technologies which will be used to detect, educate and modify drivers/operators use of noisy engine brakes. The three types of equipment are:

1. Fixed noise camera sites – A pilot was constructed at Mt Ousley and has been operational since November 2007.
2. Purpose built trailers – which will be a self contained relocatable noise camera system designed for 24 hour operation at locations throughout NSW.
3. NGARA – a hand held sound level meter that records audio noise only.

The new equipment will be deployed to engine brake hot spots.

What you can do

You can reduce engine brake noise around residential areas by:

• Installing a muffler that is specially designed to reduce engine brake noise
• Ensuring that your exhaust system is in good condition
• Turning off noisy engine brakes in built up areas.

Penalties

Penalties apply to both drivers and operators of noisy vehicles. Traffic infringement notices and defect notices can be issued when mufflers are missing or noise levels exceed set limits.