Building products with asbestos in them are putting builders at deadly risk, a new report commissioned by the Department of Labour says.

The report, obtained by NZPA under the Official Information Act, says many builders would not know asbestos if they saw it.

And while local manufacturing of those products ceased in the late 1980s, builders might also be at risk of imported goods from countries where there is no such ban.

New Zealand has a ban on importing raw asbestos but no ban on importing asbestos in goods as long as they are labelled, and no testing for them at ports.

The report's author is former national operations manager for Occupational Safety and Health, Mike Cosman .

Now a consultant, Mr Cosman said he knew of several unlabelled imported products in recent months that had tested positive for asbestos.

They included roofing materials, flooring and even tape.

But he said there was no way of knowing how much was coming into the country at the moment. Much of it is from southeast Asia, where there are no constraints on manufacturing with asbestos.

"There is little rationale for not introducing a ban as safer alternatives are available for the vast majority of uses."

New Zealand factories stopped making building products containing asbestos in the mid-1980s after the fibre became clearly linked with respiratory illnesses and cancer.

Asbestos is deemed safe if intact. But builders and home renovators are still vulnerable to exposure if they unknowingly disturb old housing materials with asbestos in them.

Mr Cosman 's report also found low awareness of asbestos in the construction industry.

"The older workers tended to think asbestos was yesterday's problem, that it had all been sorted in the 80s, and younger workers, of which there were an increasingly number in the industry, know nothing about it."

The Department of Labour said it was carrying out a wider review of asbestos handling in the workplace, which might include a ban on imported asbestos products.

In late April, a cancer researcher said he believed one in 10 Australian carpenters born before 1950 would die of a fatal asbestos-linked cancer, mesothelioma.

Professor Julian Peto said the use of brown asbestos or amosite, and blue asbestos or crocidolite, in building products in Australia and Britain until the 1980s had been completely uncontrolled.

"Carpenters would chop it up with power saws without much concern at all."

The Australian Council of Trade Unions has called for a national inquiry to examine ways of eliminating asbestos from workplaces and homes .