HEALTH : Blood Banks Seek Donors to Solve Shortage : Recession has pared the number of workers who participate through their place of employment.

John Gamboa first gave blood seven years ago when a friend was in a traffic accident and needed 38 pints.

Since then, the 39-year-old Valinda electrician has given blood at least once a year.

“I know they need it right now,” he said. “And someday I might need some too.” But as a blood donor, Gamboa is part of a small group of Southland residents.

Of the 13 million people living in Los Angeles and Orange counties, 160,000 gave blood last year, said Barbara Wilks, spokeswoman for the American Red Cross. That’s 6,000 more donors than in the previous year, but not enough to fill the need; blood for Southern California has to be imported from other parts of the country, she said.

The shortage has been exacerbated by the recession. “The major employers who represent our big donor groups are shrinking,” she said.

Early each year, the Red Cross is low on blood. During the holidays, more people are ill and injured, so demand goes up, Wilks said; at the same time, healthy people are busier and less likely to donate.

The Red Cross likes to have at least 9,667 pints of blood on hand in hospitals and centers through Los Angeles and Orange counties. Last week, it had 6,980 pints available.

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Donation Tips

* Donors must be at least 17 years old and weigh at least 110 pounds.

* Donors must be in good overall health and not have been exposed to AIDS, HIV or hepatitis. All blood donations are tested.

* The process, from registration to mandatory resting time, takes from 45 to 60 minutes.

* The Red Cross has several donation sites in the San Gabriel Valley, including Pasadena, West Covina and Pomona. Walk-ins are accepted.

* To schedule an appointment at any site or for more information, call the American Red Cross at (800) 974-2113.