The term ‘heavy vehicles’ is applied generally to the trucks, B-doubles and road trains that transport goods across and around Australia; and it also includes buses, trams, agricultural machinery, livestock transporters, tankers, grain and delivery trucks and other long and possibly slow moving vehicles on our roads.

View South Australian heavy vehicle statistics. (PDF)

Heavy vehicles have different safety requirements to other vehicles. There are special road rules and added responsibilities that apply to both the drivers of heavy vehicles and to those who share the road with them.

Australian Road Rules for heavy vehicle drivers

A heavy or long vehicle displaying a “Do Not Overtake Turning Vehicle” sign is allowed to use either or both lanes, if necessary, to turn left or right safely, if it is safe to do so and the vehicle is within 50 metres of an intersection. You must not overtake a vehicle displaying a “Do Not Overtake Turning Vehicle” sign if it is signalling and in the process of turning, because of the high risk of crashing into the turning vehicle

To make overtaking safer where the road has only one lane each way, long vehicles must keep at least 60m apart, except when overtaking. On a road-train route, the minimum distance is 200m.

Long vehicles are 7.5m or longer, including any overhanging load. This criterion applies to most trucks and also applies to cars towing caravans or trailers.

Sharing the road with heavy vehicles

There has been a significant increase in the numbers of heavy and long vehicles on our roads over the past 20 years, a trend that is continuing in response to growing demand and supply of goods.

Sharing country roads with heavy vehicles

Drivers on country roads should take extra care when overtaking long vehicles.

Road trains can be up to 54 metres long and 2.5 metres wide, with up to three trailers and should only be overtaken with extreme caution:

• allow plenty of time to overtake long vehicles
• allow even longer in wet weather or changed road conditions
• remember that trailers or caravans may sway from side to side
• never overtake a long vehicle that is approaching a cross road. It may be hiding another vehicle which could be turning on to your road in front of it and you could find yourself in a high-speed head-on collision

Slow moving vehicles, including cyclists and large agricultural machinery, such as tractors and harvesters, may be encountered on country roads.

Remember to:

• overtake agricultural vehicles at slow speeds as they often swerve when approaching roadside posts or turning in to a property
• travel carefully when overtaking, cornering or driving over the crest of a hill – a slow vehicle may be on or entering the road in front of you

Overtaking lanes are provided on some rural highways, in particular the Dukes Highway (A8), National Highway (A1) between Port Wakefield and Port Augusta and the Sturt Highway (A20). They give drivers of faster vehicles the opportunity to safely pass slower moving vehicles.

When in an overtaking lane, you must:

• always use the left lane, unless you are overtaking
• at the end of an overtaking lane, indicate clearly that you intend to move into the other lane, giving way to any overtaking vehicle in that other lane
• when changing lanes at any time, give other road users sufficient warning by indicating clearly and giving way to vehicles in the other lane.

What you can do as a heavy vehicle driver

Drivers of buses of more than 5 tonnes Gross Vehicle Mass (GVM) and heavy vehicles of more than 12 tonnes GVM must not exceed 100 km/h even if the general speed limit is higher. Road trains are limited to a maximum speed of 90 km/h. A longer or wider vehicle may have a lower maximum speed limit as a condition of its permit of travel.

Fatigue is an important health and safety issue for heavy vehicle drivers. An Australian survey in 2000 found that 45% of long distance heavy vehicle drivers had experienced fatigue during their last trip.

Surveys and roadside tests indicate that about one in five heavy vehicle drivers use stimulants on at least some trips, to improve their alertness and driving performance, combat fatigue and cope with extremely demanding work schedules. However, it appears that their use has reduced over the last 15 years. Stimulants include:

• over-the-counter medications
• prescription medications
• illegal stimulants, particularly methamphetamine, or ‘speed’
• use of other psychoactive drugs by Australian heavy vehicle drivers is quite rare and their drink driving involvement is substantially lower than that of other drivers.