Only one person was successfully prosecuted in 2018 for escaped fires that NSW Rural Fire Services Commissioner Shane Fitzsimmons said posed a "very real and potentially deadly threat to the public", despite landowner escaped fires for permit and pile burns or hazard reduction climbing to more than 3000 in 2018 for the first time in a decade.

Not one person was convicted of a hazard reduction fire offence in 2012, Bureau of Crime Statistics data shows, despite the reported incidence of escaped landowner fires to emergency services jumping dramatically from 371 in 2011 to 1097 in 2012.

Only two people were convicted for lighting fires for land clearing without permits or authority in 2016, despite the annual escaped landowner fires reported to authorities jumping from 1514 in 2015 to 2565 in 2016.

The highest number of recorded hazard reduction fire offence convictions in a single year is three, in 2015 and 2019. The highest incidence of convictions was in 2010 and 2011, when two landowners were convicted each year for illegally lighting fires for land clearing, when there were only 338 and 371 escaped fire incidents reported to authorities.

The lack of convictions is despite years of warnings from the RFS and NSW Police to landowners in escaped fire hotspots across the state, including the Hunter, about the risk of fines and jail for serious escaped fire events.

The Bureau of Crime Statistics data shows only three of the 16 landowners convicted of lighting fires for land clearing without authority, permits or issuing notices to neighbours was fined after their cases were heard in court. Only one person over the decade was given a supervised community sentence.

Media reports across the state since 2012 show the RFS issued fines, infringement notices and warning letters to landowners for lighting fires during Bush Fire Danger Periods without a permit, or without giving notice to neighbours, or for escaped hazard reduction burns.

In July and August 2018 Mr Fitzsimmons said it was "extremely concerning" that hundreds of firefighters were forced to respond to 142 out of control hazard reduction burns lit by "irresponsible" property owners in a single July week across the state, followed by 48 illegal landowner fires over two days in August.

In August last year Clarence Environment Centre called for year-round fire permit requirements in NSW and other limits on landowner hazard reduction burns because of climate change-related more severe bushfire conditions, in a letter to NSW Police and Emergency Services Minister David Elliott.

"In the Clarence Valley, every year without fail, the RFS declares a set date for the end of their permit-free season and property owners rush to light up their properties in the nick of time before having to ask permission," centre vice president Patricia Edwards wrote.

"We are over being afraid of neighbours who light fires on a regular annual basis and let them run out of control. We are done with having to consider potential destruction of our properties, our wildlife, our lifestyles and even our homes by fires that someone else decides to light."

Mrs Edwards said she was angered, but not surprised, by the lack of prosecutions because of the toxic politics around climate change and hazard reduction, and politicians who blamed "greenies" and the National Parks and Wildlife Service for bushfires without acknowledging the extent of illegal landowner hazard reduction damage each year.

"Politicians talk about arsonists, but why don't landowners responsible for these escaped fires year after year get treated in the way they should be?" Mrs Edwards said.

In a 2008 internal report the RFS said nearly half of 500 fires each year in Clarence Valley, a traditional National Party state seat, were major fires, and "indiscriminate and irresponsible burning off practices" was a major cause.

In his reply, shortly before the start of Australia's catastrophic bushfire season, Mr Elliott said he referred the letter to the RFS.

Former Hunter and Central Coast RFS volunteer fire investigator Rick Miller said the push by National Party politicians for greater freedom for landowners to do hazard reduction burns failed to acknowledge the current known and serious risks posed by careless and reckless landowners.

"If you're going to talk about doubling hazard reduction burns, as some of these politicians are, then you're going to have to get real about the amount of illegal burns that are already occurring without real penalty," Mr Miller said.

The RFS had been taking landowner escaped fires more seriously in recent years but in the past it was a sensitive issue, "partly because they depended on many of the landowners to be volunteer fire fighters", Mr Miller said.

"Clearly they have to do more about investigating and prosecuting these cases because the figures show the warnings and fines aren't working."

The RFS NSW was contacted for comment. Deputy Premier John Barilaro's office was contacted for comment.