Line 10 1-gallon jugs of milk end to end and that would equal the amount of blood Joseph Holtzmann will have donated as of May 17 at the next blood drive.

With eight pints in each gallon and each pint helping three people, that's 240 lives Holtzmann, a Kahuku High & Intermediate School teacher, has helped with his regular donations every eight weeks.

"Luckily they don't take it all at once," said the 44-year-old Holtzmann. "It all started at a blood drive when I was at Damien High School. Then it sounded like fun because we got out of school."

Holtzmann will be the star donor May 17 when the school's Health Services Academy hosts a blood drive on campus.

The health academy is an occupational program that gives students a two-year glimpse into the healthcare profession, said Kahuku teacher Krista Nielsen. The academy hosts blood drives twice a year. The last drive collected about 69 pints from about 80 donors, Nielsen said.

Student Noell Kamauoha, an 18-year-old senior, said that during the last drive she and other students made PowerPoint presentations to classes on the importance of donating blood.

"I volunteered to be the poster child for blood donation at the drive," Holzmann said.

"It's really important to give because Hawai'i has to rely upon its own people for blood donation because it takes so long to fly blood into the state."

That knowledge has turned into a regular donation schedule, especially during the past 15 years, Holtzmann said, when he makes a donation every eight weeks or so.

Stephanie Rosso, director of communications at the Hawai'i Blood Bank, said there are thousands of blood donors at the 10-gallon mark. The top donor in Hawai'i has given 264 pints — 33 gallons, Rosso said.

"We have a core of donors who have latched onto this as their way of helping their community," Rosso said. "Basically you can save three lives in an hour. I hope others will consider donating."

Only 2 percent of the population donate blood in Hawai'i, Rosso said, and the majority give only once.

For people like Holtzmann, it's a no-brainer.

It's quick and nearly painless and he gets to eat ice cream and doughnuts afterward offered at the Blood Bank.

"I'm O-positive," Holtzmann said. "They love my blood. I feel proud of the fact that I've donated blood."

O-positive blood can be used by all blood types, he said.

"If you start donating blood in high school, it becomes a life-long habit," Holtzmann said. "And it might even improve your golf game."

Reach Suzanne Roig at sroig@honoluluadvertiser.com.