Students are being kept inside and sport activities have been cancelled across the city as smoke conditions worsen.
Orange had the worst air quality in the state on Monday morning as smoke from bushfires in Wollomi National Park and Kanangra-Boyd National Park blew across the Central Tablelands, combined with the fumes from a March Street fire at about 6.30am.
Orange's air quality index was listed as 892 by the Department of Planning, Industry and Environment on Monday morning. Air quality is considered hazardous when the AQI reaches 200.
It was briefly overtaken by Armidale around lunchtime but still finished the day the state's worst AQI of 964.
Indoor basketball games have been cancelled for Monday night as have the Central West AFL's touch AFL9s games, while Orange District Junior Cricket Association has cancelled its Woolworths Junior Blasters program.
The ODJCA has cancelled several games and training sessions over the past month due to air quality.
Many schools across the city kept students inside on Monday, with Orange East Public School cancelling sport classes and not allowing children outside during recess and lunch.
The school also advised students with breathing difficulties to seek advice from medical providers and "consider carefully if your child is well enough to attend school".
Department of Education media liaison officer Grant Hatch said "the well-being of students is of the highest priorities at local public schools".
"Decisions about actions to take to enhance students' well-being while schools are impacted by bushfire smoke is taken on a school-by-school basis as the effects of smoke will vary between schools," he said.
A fact sheet was distributed to all public school principals last week suggesting ways to minimise exposure, which included staying indoors, using air conditioners in rooms and consideration of sporting activities.
"Schools have also received advice about symptoms and conditions that can be triggered by the bushfire smoke and they are taking particular care of identified students and staff," Mr Hatch said.
"Where the bushfire danger is more immediate, schools and the Department have been working closely with agencies including the Rural Fire service, Health, police and local councils."
Canobolas Zone Rural Fire Service suggested people stay indoors where possible, and for those forced to stay outside to purchase face masks.
Weatherzone.com.au is predicting hazy conditions to continue into Wednesday, with winds staying northerly and easterly until a westerly wind kicks in on Wednesday afternoon.
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