FILE - In this Aug. 15, 2019, file photo, marijuana grows at an indoor cannabis farm in Gardena, Calif. The U.S. House of Representatives passed a bill Wednesday, Sept. 25, 2019, that would grant legal marijuana businesses access to banking, a measure that would clear up a longstanding headache for the industry. (AP Photo/Richard Vogel, File)

JOHANNESBURG - Most company policies cater for the use of illegal substances while at work, but these need to be updated to reflect new regulations after the use of cannabis at home was legalised, with the potential for employees to arrive at work under its influence, a human resources expert said on Monday.

South Africa's Constitutional Court has de-criminalised private consumption by adults of cannabis, also known as marijuana among other names, but laws prohibiting use the drug outside one's private dwelling and buying and selling it still remain.

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Nicol Myburgh, head of the HR business unit at human resources company CRS Technologies, cited studies showing that cannabis could affect an employee’s occupational capacity, including performing tasks more slowly, performing poorly when handling routine, monotonous tasks and difficulty in multi-tasking, taking instructions from superiors, making crucial decisions and operating machinery and/or motor vehicles.

"From a policy perspective, there is no difference between taking cannabis and drinking at home. Consequently, the approach is the same as if the employee arrived at work under the influence. Of course, the challenge lies in proving that the employee is under the influence of cannabis while at work," Myburgh said.

He said workplace policies should explicitly state the repercussions for arriving at the work under the influence, be it from alcohol usage, cannabis, or any other mind-altering substance.

“Considering that cannabis is no longer an illegal drug, company policies must be adapted to encompass employees being under the influence of mind-altering substances. Alternatively, the alcohol usage policy should be expanded to include cannabis,” Myburgh said.

- African News Agency (ANA)