Bloodworks Northwest is sending out an urgent appeal for donors with type O blood after their inventories dipped to emergency levels earlier this week.

Normally, Bloodworks Northwest and their locations in Bellevue and around King County keep a four-day supply of type O blood on hand. However, the organization announced yesterday that their supplies had dipped “alarmingly low” and they only have a one-day supply on hand.

“We expect donations to fall by about 15 percent during summer — with schools and colleges on break and donors on vacation,” a Bloodworks Northwest spokesperson said in a statement. “This year, the drop off has been closer to 25 percent.”

Type O negative blood is considered the universal blood type and can be transfused to any patient suffering from trauma when they are rushed to a hospital with no time to type that person’s blood. Nearly half of the population has type O blood.

Across the country, blood donation organizations are experiencing a shortage in supply, Bloodworks Northwest added.

Bloodworks Northwest will be located at 1021 112th Ave. until Aug. 29. They will move into a new location on 132nd Avenue Northeast on Aug. 30.