Shearing contractors in the south have been told they must unite to stamp out drugs, which are said to be rife in the industry.

Southland is in its peak summer shearing season, and two years on from an initial campaign to clean up the industry, the New Zealand Shearing Contractors Association is making another push on standards.

The initiative comes almost two years after Southland trainee presser Troy Macfarlane Adamson, 17, died when his vehicle crashed after he fled a shearers' party. He had cannabis and alcohol in his system.

The association is urging contractors and shearers to take responsibility, particularly to prevent shearing-related road crashes.

"Our biggest worry is a vehicle accident with one of our crews," association president Barry Pullin said.

"Until something happens, they are 10-foot tall and bulletproof and it's someone else's problem," he said.

Shearers, shed hands, pressers, contractors and farmers needed to do their part.

There should be zero tolerance for drugs, alcohol, speeding and driving in unsafe vehicles. Individuals had to take responsibility for themselves, including wearing seatbelts.

"Every single one of them deserves to be home with their family," he said.

"It's a stupid waste of life."

Davis Shearing Contractors owner Jason Davis said some contractors were cutting corners, but many were stepping up against drugs and alcohol.

"Safety is paramount to us; getting them home, and to and from work every day is one of the biggest problems we face," Mr Davis said.

The company has zero tolerance for drugs, and zero tolerance for drink-driving.

The company had a breathalyser and workers caught under the influence would be sacked, he said.

A big problem was farmers offering alcohol to workers, but farmers had been sent letters asking them to keep it to a minimum, Mr Davis said.

Hillis Shearing owner Sharon Hillis said she backed the concept of zero tolerance for drugs and alcohol but all contractors would have to be on board.

"We do have a problem industry wide as far as drugs, it's rife in the industry," she said.

"It's got to be all contractors; if some don't then the shearers will go work for them."

The association is working with Federated Farmers, the police, ACC and the Ministry of Business, Innovation and Employment to look at travel guidelines and how to raise awareness.

Mr Pullin said more was being done to encourage contractors to get tough on drugs and alcohol, but only the minority were on board. There was a lack of respect and care for fellow workers, and a mistaken belief that it would not happen to them, he said.

terri.russell@stl.co.nz