Police, firefighters, paramedics and other emergency workers launched their annual Sirens for Life campaign Wednesday, calling on the public to help make a difference with a simple blood donation.

Whether they’re tending to victims of violent crime or car crash survivors, first responders are constantly reminded of the vital importance of donated blood.

That’s why every year, they partner with Canadian Blood Services to raise awareness about the need for new donors.

“This is truly a life-saving gift,” Vancouver Police Const. Brian Montague said while kicking off the campaign at a blood clinic on Oak Street.

“We encourage our members, we encourage other first responders and we encourage our family and friends to come in.”

A single person who is seriously injured in a car accident can require up to 50 blood donations, according to health officials. Unfortunately, summers typically see donation numbers slip.

Earlier this month, Canadian Blood Services said it requires 32,000 donations by Labour Day to meet patient needs across the country. Though the organization is moving toward that goal, David Patterson, director of donor relations, said there’s still a long way to go.

Patterson said CBS is looking for all blood types, but O-negative is particularly important because anyone can receive it.

“O-negative is the universal donor,” he said. “If someone is severely injured and gets rushed to the hospital and the hospital doesn’t have time to match their blood, they’ll be given O-negative.”

Unfortunately, only about seven per cent of Canadians have O-negative. The most common blood type is O-positive, accounting for about 39 per cent of the population, which means it’s always in high demand.

Canadian Blood Services said the standard donation is about 450 millitres, a little less than two cups, which it describes as a “small portion” of the roughly five litres of blood in the body of the average adult.

Most people who are in good health and at least 17 years old are eligible to donate, though there are height and weight requirements for people between 17 and 23.

Gay men are also required to wait a set time from their last sexual experience with another man to donate, though that deferral period has been reduced, effective this month, by Health Canada. They must now wait one year instead of five years. 

To learn more about eligibility or to book a donation appointment, visit the Blood.ca website.