A lower percentage of New Zealanders tested at work last year were found with traces of illegal drugs in their system.
Private drug testing company New Zealand Drug Detection Agency (NZDDA) conducted 81,410 tests for drugs in New Zealand workplaces during 2013, with 5.5 per cent returning a non-negative test.
This was down on 6.4 per cent in 2012 when 68,346 tests were done.
A non-negative test means a drug was found in the person's urine and still had to be confirmed by an accredited laboratory for confirmation testing.
The most commonly detected drug was cannabis, with 71 per cent of all non-negative tests indicating its presence.
NZDDA chief executive Chris Hilson said it was pleasing to see a drop in the number of non-negative results.
"We believe this can be attributed to a number of factors including an increase in employee awareness regarding the dangers of drug and alcohol use in the workplace, and also understanding the potential for serious or fatal accidents," Hilson said.
"Also more random testing is a major deterrent factor within the workplace."
Cannabis was detected most frequently in "traditional" cannabis-growing areas such as Northland, Waikato, Bay of Plenty and the North Island's East Cape, Hilson said.
Synthetic cannabis was tested for, for the first time this year.
More than 12,000 tests were carried out for the drug, but it accounted for only 3.3 per cent of all non-negative tests.
Two of the more safety-sensitive industries, construction and forestry, saw decreases in non-negative test results in 2013 compared to 2012, returning 14 per cent and 8 per cent respectively.
Mining saw a slight increase in non-negative tests but remained relatively low at 4 per cent of all tests done.
However, it did have the highest rate of synthetic cannabis use of any industry, with 10 per cent of all non-negative tests in mining indicating a presence of the drug.
Those three industries all increased the number of tests they conducted, as did some of the more "white-collar" industries, Hilson said
"Not only are employers in safety-sensitive industries increasing their workplace drug and alcohol testing, but also more white-collar employers are carrying out testing for drugs and alcohol.
"Whether you're in the forestry industry, run a transport business, or in the financial sector, it's vital for your organisation that your employees are working unimpaired and without risk."