The Ministry of Education has provided schools with air cleaners and carbon dioxide (CO2) monitors to help them keep ventilation at safe levels.
Guidelines have been issued to help keep spaces ventilated, which include opening windows and doors to increase air flow and preheating classrooms to offset the cold.
Maniototo Area School principal Joe Ferdinands said it got so cold at the Ranfurly school that ventilating rooms throughout the day was a health risk.
The senior pupils had new facilities with modern heating, but the junior block was old and running on a slow diesel boiler.
The temperature often peaked about 8degC during the day and all the heating from the boiler "simply vanishes" from the room when the windows were opened.
The result was a classroom where pupils, some as young as 5, could not focus on their learning because they were so cold, he said.
Ranfurly holds the record for the lowest temperature in New Zealand history.
The guidelines were designed with a one-size-fits-all solution, but did not keep in mind the severity of Central Otago winters, Mr Ferdinands said.
The school was running the one air purifier supplied by the Ministry of Education, but it did not work well enough by itself and the windows still had to be opened periodically throughout the day to keep up with the CO2 monitor.
It was good the ministry was taking action, but the guidelines were not conducive to learning, which was the main focus of a school.
Other schools in the region were not having as much trouble with the guidelines.
Clyde Primary School’s Stephanie Kitto said ventilating the classrooms had not been much of a disruption and could mostly be done between classes.
Cromwell College principal Mason Stretch said it had not had many issues with the guidelines yet, but the depths of winter were yet to come.
The school had a new woodchip boiler, which kept classes warm, even with good air flow.
It had changed the school rules so pupils were allowed to wear jackets inside if they felt cold.
Ministry of Education infrastructure and digital leader Scott Evans said good ventilation practices needed to be balanced with keeping rooms at a comfortable temperature.
Provisions were available for additional air cleaners and funding for urgent building maintenance improvements to support good ventilation.
