Volunteer firefighters battling the unprecedented mega blaze across NSW have been forced to turn to crowdfunding to raise money to buy essential safety gear.

Treasurer of Copacabana Rural Fire Brigade Joe Arena said “completely exhausted” firies who had been working around the clock were suffering using dust masks to protect their airways, ABC Central Coast reported.

Mr Arena said he was “horrified” firies had no option but to use the ineffective masks, that were supplied to them through the NSW Rural Fire Service. The brigade has turned to the public to raise funds to buy more masks.

Their fundraising drive comes as Prime Minister Scott Morrison on Tuesday dismissed the idea of paying volunteer firefighters.

‘‘It is not a matter that's currently under consideration by the government,” Mr Morrison said during a press conference in Sydney shrouded by thick bushfire smoke.

“Yes they're tired, but they also want to be out there defending their communities,” he said after praising the efforts of the firefighters.

View photos Joe Arena has started fundraising for better face masks for firefighters. Source: Facebook More

Mr Arena said crews manning the three Copacabana trucks for the past two weeks have been fighting giant fires in Hawkesbury and Central Coast areas.

“Our brigade has been desperately trying to protect homes and property – completely exhausted - and I’m horrified to say this, using NSW Rural Fire Service issued dust masks to protect our airways.

“In defence of the RFS, these are unprecedented conditions, on a scale no one could have anticipated, but we have no choice but to go out and fight fire with what we have.”

With conditions showing no signs of easing any time soon, Mr Arena has set about raising money to maintain a supply of better quality masks.

He hopes to have enough to keep eight members who operate the “heavily used bush trucks” protected from the thick smoke and ash.

View photos Mr Arena said the supplied masks from RFS did not serve their purpose. Source: Facebook More

Volunteers getting worn out, says former fire chief

Former Fire and Rescue NSW commissioner Greg Mullins said he fears for the welfare of volunteer firefighters.

Mr Mullins said crews were working 12-hour shifts and with many travelling two hours each way to reach fire grounds, meaning they faced 16 hour days.

"Everyone is getting pretty worn out and, in my experience, that's where all the bad stuff happens," he told AAP.

"The troops, if they're worn out, you get to a stage where it just overwhelms everyone, so that's a worry."

The fire danger remains elevated across large chunks of NSW despite a southerly wind change bringing temperatures down as it swept up the coast on Wednesday.

The Rural Fire Service, meanwhile, has confirmed more than 720 homes have been destroyed over the fire season.

“Unfortunately the number of homes destroyed in this fire season continues to rise - now 724 homes confirmed lost and 2.7 million hectares burnt,” RFS deputy commissioner Rob Rogers said on Twitter on Wednesday.

With AAP

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