One of the country's largest training institutes is understood to be ditching a mandatory drug testing regime, over claims it's seen as a "barrier to education".

The Bay of Plenty-based technology institute had trumpeted its mandatory tests, at a time when former Prime Minister Bill English was lamenting high levels of drug-use among young workers.

But now, with National out of government and mandatory drug-testing out of favour, Toi Ohomai Institute of Technology has quietly ditched the drug tests.

National's tertiary education spokesman Paul Goldsmith warned that it was impossible to keep workers safe in high-risk industries without drug-testing.

Generally, he said, it should be up to education institutes whether they introduced mandatory drug testing. "However in high risk courses like construction or forestry, it's important that everyone is able to exercise judgment and show responsibility so you'd expect that everyone is drug free and the only way to know that for sure is by testing."

Toi Ohomai was formed from the merger of Rotorua's Waiariki Institute of Technology and Bay of Plenty Polytechnic last year. Its trades department teaches carpentry, electrical, engineering, automotive and collision repair.

Mother-of-two Katherine Page was a Level 3 carpentry student this year, and is firmly in favour of the test. "You need to be able to trust your fellow students and make sure they're fully alert," she cautions. "Because it could impact your life, not just theirs, if they're on drugs."

The mandatory testing was done on the Rotorua, Whakatane, Taupo and Tokoroa campuses.

"I think it was a good thing," Page said, "especially being on a building site with a lot of hazards and dangers. If you were on drugs that would've made it 10 times worse."

She believes the regime made the course safer – and thinks it could be taken even further.

"It probably would have been a good idea to not just do the first one, but also random ones throughout the year."

At the time, the Institute trumpeted the compulsory tests, stating it had seen a significant lift in the calibre of its student groups.

But staff have been told the practice is unlikely to continue, sources say. It comes against a backdrop of a major, ongoing restructure across Toi Ohomai, which is understood to have seen more than 100 employees depart over the past six months.

Former head of the trades department John Kelly, who no longer works at the Institute, believed the change in stance had proved contentious.

"I've bumped into a few staff members that have registered their disappointment at what impact that will have. I think the key concern is for that genuine student – the one who's not bringing outside influences to the training environment, influences which create disruption and disengagement."

The results for the first semester in 2016 saw an 8 percent fail rate – mostly for cannabis, but that had dropped to zero at the most recent round of testing in May.

Kelly said that while the testing did cause an initial decline in enrolment numbers, it was overwhelmingly supported by industry, and teaching staff. "We saw students who were there for very genuine reasons and they weren't distracted by any outside influences, or even their own recreational habits. They just seemed to be a lot more focused, a lot more dedicated."

The practice of drug testing trade students has become quite common amongst training institutes, according to The Drug Detection Agency (TDDA) CEO, Kirk Hardy.

"It's setting an expectation from the word go – saying 'be prepared' because this is what to expect in the workplace, because safety is such an important issue these days."

He's never come across an institute that's back-tracked on testing, once it's been introduced.

"Even though they find it hard in some instances to get drug-free students, no-one's ever said 'we're prepared to waive that – because we can't get bums on seats,' sort of thing. They take it really seriously."

TDDA conducted more than 140,000 drug tests for workplaces, training centres and job-seekers in 2016 – up from 112,000 the year before.

The cost for each standard test is around $75 to $80.

Toi Ohomai wouldn't address direct questions about whether it planned to drug-test all trade students in 2018.

In a statement, it said it did not have any policy concerning compulsory drug testing, adding that it was "not in the business of putting up barriers to education."

"Our goal is to prepare students for the workforce and we do this by providing safe working environments….We will continue our existing practice of drug testing any student who appears to be impaired by drugs or who are at risk to themselves or others while undertaking practical training."

It said in some courses, mandatory drug testing is a requirement – such as road transport and forestry.

John Kelly said Toi Ohomai's Regulatory Framework allows for mandatory testing, if there was a willingness to do it.

But he points to student numbers as being critical to revenue, and therefore success. "Any impediment to that would probably be reconsidered."

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