Operation Convey was established by officers from the Traffic and Highway Patrol Command to target unsafe behaviours from heavy vehicle drivers on the Cobb, Sturt and Mid-Western Highways, the latter of which links the Central West with southern areas of the state.

The Mid-Western Highway runs through Blayney and adjacent to Orange and eventually links with the Great Western Highway on the way to Bathurst, with the four-day operation coming to an end on Wednesday.

Officers stopped more than 500 heavy vehicles as part of the operation and of 221 random, roadside drug tests seven positive results were returned. More than 200 infringement notices were issued for a range of offences relating to fatigue, load restraints and dimensional breaches.

A further nine defects and eight cautions were issued against heavy vehicles.

Acting Inspector Brett Collins from the Traffic and Highway Patrol Command said recent incidents sparked the police operation.

"Police held concerns following several serious heavy vehicle crashes on regional roads," he said.

"Driver error, inadequate load restraints and poor mechanical standards were all contributing factors to recent crashes, and this operation really focused on targeting those unsafe behaviours.

"We strongly encourage drivers of heavy vehicles to ensure they are practicing safety at all times. This means checking your load, taking regular breaks and complying with road rules and relevant legislation.

"We're also putting employers on notice; if we see heavy vehicle drivers doing the wrong thing you can expect a knock on the door and further investigations to take place.

"Heavy vehicles remain over-represented in serious crashes, and we want to reduce this as much as possible."

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