Australians in smog-wreathed cities would have access to stockpiles of smoke-filtering masks under a Greens policy to establish a climate emergency national medical stockpile.

"It's almost impossible to avoid, it can claim lives, and it hurts everyone's quality of life," Greens leader Richard Di Natale said. "Already one person has died in Canberra, and the public health impacts on the broader population won't be known for months."

Visitors to Parliament House were forced to wear face masks after smoke from bushfires blanketed Canberra in a haze. Credit:Alex Ellinghausen

The government has made more than 1.8 million P2 masks, which help wearers breathe in fewer hazardous smoke particles, available to people living on the front lines of the fires or who are particularly vulnerable to the effects of smoke inhalation.

The masks come from an existing medical stockpile, but the Greens want to go further, advocating for the much wider distribution of masks to people in major cities.