MINNEAPOLIS — 3M Co. says global demand for N95 masks continues to far exceed supply.

The Maplewood-based conglomerate corporation says it has doubled production of N95 masks this year.

But, with too few N95 respirators to go around, nurses and other health care workers are being force to reuse the masks even though the coronavirus can live on surfaces for up to 72 hours.

Hospitals are taking steps to extend the use of a single mask, including using ultraviolet light to kill the virus or treating them with vaporized hydrogen peroxide.

Used masks can also be placed in separate paper bags where they can air out until any virus dies, according to the Centers for Disease Control and Prevention.

Health care workers, including hospital staff, make up about 10% of Minnesota’s 35,549 confirmed cases, officials said.

That number of positive cases grew by 523 cases Sunday, according to the Minnesota Department of Health.

Eight more people have died of COVID-19 in Minnesota, bringing the number of deaths to 1,425 across the state, health officials said.