As firefighters battle to gain control of more than 100 bushfires burning across the state, the smoke from these massive blazes continues to settle across the region.

At 7am on Wednesday, the numerical rating for the region was 769 which is 'hazardous' on the NSW Department of Planning, Industry and Environment (DPIE) website.

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This level is almost four times the DPIE's minimum to be registered as hazardous.

The DPIE said everyone, especially people with heart or lung disease, should avoid outdoor exertion and stay inside as much as possible.

"If you have symptoms rest and use your reliever medicine," the warning states.

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"If symptoms persist, seek medical advice."

The out-of-control 415,104 hectare Gospers Mountain bushfire (burning east of Lithgow) and 149,651 Green Wattle Creek bushfire (burning in the Kanangra-Boyd National Park) continue to create large volumes of smoke.

While the 2302 hectare Palmers Oaky bushfire also remains out-of-control.

Stay up-to-date with fires in your area at Fires Near Me.

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