Southern Tablelands operations officer Lachlan Gilchrist was responding to Monday's Goulburn Post article in which a district resident, Hilary Myers, questioned the wisdom of dropping the devices over the Currowan blaze. It was burning 1-1.5km away from her Long Point Lookout Road home, in the gorge. Mrs Myers said she was alarmed the strategy was employed in such hot conditions, describing it as a "reckless decision" which she understood Tallong Brigade did not support.

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But Mr Gilchrist said this was not the case.

"The brigade was on board with it and it was actually part of a broader fire containment strategy, which was done in consultation with and the support of the local brigade," he said.

"I appreciate community concern about more fire in the landscape but the decision was made that this was the most effective strategy to contain (the Currowan blaze). We will not put more fire on the ground unless it is safe to do so and proves meaningful."

RFS Southern Highlands community safety officer, Inspector David Stimson, also said the community was informed about the incendiary devices at a barbecue hosted by Tallong RFS on Sunday.

The Currowan fire stands at 314,339 and is burning south-east of Marulan and near Tallong in national park. The incendiary devices, constituting small balls of chemical that ignite on impact, were dropped on Monday and Tuesday to burn out the area down to the Shoalhaven River to reduce risk of a major flare-up in coming days. Aerial water bombers are on hand throughout. On Wednesday, the RFS reported the fire "was slowly working down towards the river."

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"It is proving to be very helpful and the fire remains well within containment lines," Mr Gilchrist said.

He said the devices were also dropped over the Green Wattle Creek fire as a way of burning out areas that were unsafe for crews to access in the event of a flare-up.

The Service is bracing for high 30 and 40 degree temperatures in coming days. Crews have been using this week to reinforce containment lines and douse active fire spots on the Currowan, Morton and Green Wattle Creek blazes. Around Tallong, a tactical backburn continued along Caoura Road, east of Blues Point Road on Wednesday.

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On all firegrounds, aviation is accessing difficult to reach areas and strike teams are working. Mr Gilchrist was "reasonably confident" these actions would prove highly useful in the hot and challenging days ahead.

The RFS is predicting 'very high' and 'severe' fire conditions across the southeast.

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