Tasmanian Occupational Health and Safety Services owner Tony Walters said he had not seen an increase in the number of people testing positive to drugs  but had seen a switch in what people were using.

‘‘What we have seen is a switch away from the THC to other drugs,’’ Mr Walters said.

‘‘They tend to be amphetamines, methamphetamines, prescription drugs.’’

Mr Walters said the shift had been in the past two years and was across the board for all occupations.

Many Tasmanian businesses, from office-based to construction companies, drug test their employees.

Mr Walters said drug testing was a way to keep workers safe and deter people from taking drugs when it could affect them at work.

While most businesses would not confirm how many employees had tested positive in the past year, one Northern Tasmanian building company did.

Fairbrother chief executive officer Craig Edmunds said the company had seen no positive drug test results in the past year.

‘‘We have been drug testing for at least five years and probably average one or two positive results a year,’’ he said.

Fairbrother tests new employees, does random monthly tests and ramps up its testing around Christmas time and among employees who work away from home.

Mr Edmunds said any workplace that involved high-risk activities had an obligation to test its employees.

‘‘As an employer, you have to provide a safe workplace,’’ he said.

Employers can choose between saliva and urine drug and alcohol tests.

Saliva tests are less invasive and usually only detect drugs taken within a few days.

Urine tests can give positive results for up to 90 days after the drug is taken.

Incat Tasmania human resources manager Richard Lowrie said the shipbuilding company did saliva testing for the first round of all drug and alcohol tests.

He said the company was not about stopping its employees from what they did when they were not at work.

‘‘It’s not about trying to be disciplinarian, but certainly  don’t come under the influence of that to work,’’ Mr Lowrie said.

‘‘Saliva testing allows it to get out of their system before they come into work, therefore they are mentally aware and able to do their job.

‘‘Other workers have to know that they have a right to come to work and go home at the end of the day.’’

Mr Lowrie said that if employees tested positive to drugs, they were sent home and had to have another test before they started the next day.

‘‘If they test positive three times in a 12-month period, we have the right to terminate employment,’’ Mr Lowrie said.

Other companies have similar policies.

Vos Construction chief executive Adrian Bott said any employee or contractor who failed a drug or alcohol test was removed from the workplace until they were fit to return.

‘‘On the first positive test ... the person will be encouraged to undertake an appropriate educational course,’’ Mr Bott said.

‘‘A second positive test by an employee will result in a formal warning that their employment is in jeopardy of being terminated, and we encourage them to undertake rehabilitation.

‘‘A third positive test within two years of the first breach  will result in the loss of employment.’’

Bell Bay Aluminium was unable to confirm the number of positive drug tests it had seen, but said it required employees, contractors and visitors to submit to an alcohol and drug test if:

●A health, safety or environmental incident had occurred.

●There was an ‘‘observed behaviour’’ which indicated a person may be under the influence of alcohol or other drugs.

●As part of random or blanket testing procedure (carried out daily).

●If there was other information or circumstances which indicated an individual may be under the influence.

The Hobart City Council made headlines earlier this month when aldermen exempted themselves from its workplace drug testing regime, which will be imposed on all other council staff.

Launceston City Council general manager Robert Dobrzynski said Launceston aldermen were not drug tested  but had ‘‘been observing the recent debate at the Hobart City Council with interest’’.

The University of Tasmania, which is the second-biggest employer in the state, does not drug test its employees.

Independent Tasmania Senator Jacqui Lambie on Tuesday called for welfare recipients to be drug tested, saying: ‘‘Dole payments are meant to be a social safety net to protect you from the hard falls in life, not a jumping castle for you and your mates to party on’’.

 Email: mdadson@fairfaxmedia. com.au

Twitter: @ManikaDadson