APPEA chairman Colin Beckett told the association's annual conference in Perth this morning that APPEA has had an Environmental Code of Practice for more than 30 years.

"We were early movers and we continue to take our stewardship role seriously," he said in his opening address.

"We clearly recognise that our environmental credentials are critical to our industry's on-going community and government support.

"The Code provides a leadership mechanism on environmental performance for all APPEA members, while also sending a clear message to all stakeholders about the industry's own expectations with regard to its environmental performance."

APPEA is consulting with World Wildlife Fund Australia, the Australian Conservation Foundation and environmental regulators from around the country to finalise the new code, to be released at APPEA's environment conference in October.

In mid 2007, then Federal Environment Minister Malcolm Turnbull released new seismic exploration guidelines that require vessels to stay at least 2km away from whales while undertaking surveys. Under previous guidelines, a distance of 3km was required.

Beckett said the recent release of a significant new report by the US National Marine Fisheries Service quantifying the effects of sound generated by seismic exploration on marine mammals should serve to further evolve these guidelines.

Of the roughly 400,000 signals analysed from surveys carried out in Australia over the past few years, only eight were found to have exceeded the behavioural disturbance threshold and not one has exceeded the physical impact threshold as defined by the United States report, according to Beckett.

"APPEA is unreservedly confident that the industry's operations do not cause any significant effect on marine mammals," he said.