Want to give blood? There’s an app for that.

The Red Cross Blood Donor App (American Red Cross)

It happens every two seconds: a person needs donated blood or platelets to survive a surgery, cancer treatment, a traumatic injury.

But blood stocks aren’t always high enough, especially during the winter when the holidays and nasty weather make some donations drop off. And each year, only 3 percent of the population actually gives blood, according to the American Red Cross, the organization responsible for 40 percent of the nation’s blood supply.

If you’ve been meaning to donate blood but haven’t, give the Red Cross Blood Donor App a try. Available for iPhone and Android, the app makes the process more convenient.

It helps you find places to donate and set up appointments. It also stores data about your blood donations so you can see how much you’ve donated and when it’s time to donate again. The app sends out alerts about shortages so you can give blood when it’s needed most. And it even lets you recruit new blood donors, creating a team of your friends and keeping track of your total donations.

Another benefit: The app can save you up to 15 minutes when you donate with RapidPass, an electronic questionnaire that can cut down on wait time at the donation center.

Your blood is put on ice at the donation center. It then is taken to a processing center and spun in a centrifuge, separating into red blood cells, platelets and plasma. These materials are stored in standardized units.

After being tested for disease and blood type, eligible units are stored and distributed to hospitals. Red blood cells are used within 42 days and platelets within five days. Using the app, you can find out when your donation is taken to a hospital.

Want to get going? Text BLOODAPP to 90999 or search in your app store.

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Your blood could be worth a lot