NSW Premier Barry O'Farrell has denied hunters will be allowed to use silencers on guns when shooting feral animals in the state's national parks.

Fairfax Media reported the proposal, which was leaked in a draft assessment report, would require loosening the state's prohibition on silencers, a ban designed to stop them falling into criminal hands.

But Mr O'Farrell has rubbished the report.

"There will be no change to the regulation of silencers to allow for the operation of pest eradication measures in national parks," the premier said in a statement.

National Parks Association of NSW campaign coordinator Justin McKee has said silencers were a safety risk as they removed people's awareness that hunting was taking place nearby.

From May, 77 national parks and reserves will be open to amateur hunting of feral animals.

The Public Service Association, which represents park rangers, called on Mr O'Farrell to release maps of all proposed "Zone C" unsupervised hunting areas.

"Rangers are anxious to know which parts of their parks will be opened to unaccompanied hunters, as reports emerge that ... rangers will be protected by nothing more than a high-vis vest," PSA General Secretary Anne Gardiner said in a statement.

Rangers had been told most of the total national park land opened to amateur hunters would be Zone C, Ms Gardiner said.

"The community has not received a definitive list of which national parks will include unsupervised hunting and where exactly these unrestricted hunting zones will be located," she said.

Opposition environment spokesman Luke Foley said the fact silencers were considered in the draft risk assessment report proved the hunting program had become a farce.

"There's one simple solution here, Mr O'Farrell can abandon this very bad policy of opening our national parks to amateur hunters," Mr Foley told reporters in Sydney on Tuesday.

He said the report also confirms Environment Minister Robyn Parker is "not up to the job" of managing the rollout of the program.

Mr Foley repeated opposition calls for Mr O'Farrell to take personal responsibility for the policy and commit to resigning if any person is shot by an amateur hunter in a NSW national park.

An employee at the company operating the balloon said the tourists were from Korea, Japan and Britain, as well as one Egyptian.

"This is terrible, just terrible," an employee told AFP, declining to give her name.

"We don't yet know what happened exactly or what went wrong."

The balloon which was carrying 21 people was flying at 300m over Qurna, in Luxor's West Bank, when it caught fire before exploding, a security official said.

Two survivors, including the balloon's pilot, have been taken to hospital, he said.