United Blood Services has issued an urgent appeal for type O-negative blood.

Increased usage in recent days has caused supplies of that blood type to drop to critically low levels. Those with type O-negative blood are urgently needed to donate.

The Santa Barbara Center will be open for special hours, until 7 p.m. Wednesday and from 8 a.m. to 3 p.m. Thursday.

Donations may be made at the UBS Center in Santa Barbara at 902 Laguna St., at the corner of Cañon Perdido. Appointments are appreciated but not necessary.

Those who donate blood must be older than age 16, weigh at least 110 pounds and be in good health. Additional height/weight requirements apply to donors age 22 or younger.

Donors are asked to make an appointment by clicking here or calling 800.715.3699.

— Janna Nichols is the marketing manager for United Blood Services, Central Coast.