The TTC says it will introduce random drug and alcohol testing for employees as of March 1.

In a press release issued on Thursday afternoon, the TTC confirmed that it has given formal notice of the move to the four unions that represent TTC workers.

The procedural step comes one week after the TTC board approved a plan that will see 20 per cent of all employees in “safety sensitive positions” subject to random testing.

According to press release, a third-party provider will generate a random list of employees and conduct the tests. Employees chosen for the tests will then have to submit to a breathalyzer for alcohol and provide a saliva sample for drug testing.

“The TTC will test only for likely impairment at the time of the test. Test results will indicate a pass or fail. The TTC has no interest in what its employees do on their own time, unless it has a potential impact on the workplace,” the press release states.

Since 2010, the TTC has been allowed to subject new employees in certain positions to alcohol and drug testing. The TTC has also been able to subject employees to alcohol and drug testing when there is “reasonable cause” to believe they may be impaired.

The TTC says that it has seen a 200 per cent increase in confirmed cases of workplace impairment and test refusals between 2011 and 2015.

So far in 2016 there have been 21 instances where an employee has failed a drug or alcohol test or refused to take one.

“Random testing will act as a deterrent to those who may otherwise come to work when they are not fit for duty,” the press release states.

While the TTC has said that random drug and alcohol testing is an important initiative that will protect rider safety, Amalgamated Transit Union Local 113 President Bob Kinnear has previously been critical of the idea.

“Mr. (Andy) Byford said he doesn’t care what employees were doing two or three days ago but this testing will in fact infringe upon that,” Kinnear told CTV News in April.

According to the TTC, more than 10,000 employees will be subject to the random testing, including all operators and maintenance employees and designated supervisors, managers and executives.

The cost of implementing the program is $1.3 million.