Indoor air quality standards would lead to health benefits, experts say

A group of experts is urging the government to create national standards for indoor air quality.

A letter, published in the New Zealand Medical Journal, said there would be significant benefits for society if indoor air was more regulated.

University of Otago Professor Julie Bennett contributed to the letter and said while outdoor air quality has been monitored for decades, indoor air quality is often overlooked.

"Indoor pollutants can build up if there isn't good ventilation, so the concentration of pollutants can be a lot higher indoors than they are outdoors... People often don't appreciate that we spend up to 90 percent of our day indoors and this means we're having a prolonged exposure," she said.

Around three million people per year died worldwide as a result of indoor air pollution, Bennett said.

There were many benefits to regulating indoor air quality, such as reductions in sickness, allergic reactions, hospitalisations and moisture in homes, the letter said.

Improved air quality would also increase cognitive function and productivity in workplaces by reducing the amount of carbon dioxide circulating in office buildings.

Professor Bennett said there was no substantial data on what indoor air quality data looked like around the motu, though studies have been undertaken in homes and schools in the past.

Local construction methods also weren't helping.

"The majority of New Zealand homes rely on natural ventilation and do not have heat-recovery units, and in winter many homes cannot be heated to healthy temperatures. For these reasons, New Zealand-specific solutions are needed, and ventilation improvements should not come at the cost of healthy indoor temperatures," the letter said.

It recommended putting health front and centre of the building code and urged the government to create a national indoor air quality standard.

Whose breath are you breathing