Kerry Felstead made his first blood donation in Parramatta in 1996 while he was visiting family. He had been getting a blood test at the doctor when he was told how important his type of blood was.

"The doctor said to me 'we need this sort of blood', and I thought, 'oh well, I might start donating'. I asked my sister that day where the nearest blood bank was," he said.

"I didn't think I would get to 300 because I had a bit of trouble with my iron at about 180 and I didn't think I'd get to 200 let alone 300. But I'm quite happy about it and I've helped a lot of people.

"I rang up the head office in Adelaide and the woman told me 'oh, you helped about 900 people, you must be one of the most prolific donors at the Dubbo Centre'."

Mr Felstead is one of an estimated seven per cent of Australians - or one in 12 - who have type O negative blood. Despite its scarcity, it's in high demand as it's a universal blood type, meaning it can be used in transfusions for any blood type.

This makes O negative blood crucial for emergency transfusions and immune deficient infants.

Knowing how important his blood type is, Mr Felstead gives whole-blood every three months and plasma every two weeks.

"I'm thinking about trying to get to 500 donations ... there's a lot of sick people and a lot of sick kids and, with the plasma, I help burn patients, cancer patients and whatever else," he said.

According to Lifeblood, more than half the plasma collected each year in Australia - around 400,000 donations - comes from just 30,000 people. Their plasma is used to make 2,500 transfusions and treatments to patients every day.

Proud of his status as a blood donor, Mr Felstead has a red licence plate reading 'ODONOR' and a tattoo on his arm commemorating his blood donation milestones and reminding himself why he does it - "for the sick kids".

"My last blood donation went to Wollongong, my blood's gone to Orange, Newcastle, Port Macquarie ... so many different places," he said.

"The thing is you don't know who actually gets it. It could be a cousin. It could be a friend. It could be a relation."

Mr Felstead hopes by sharing his story and showing off his milestones he will encourage more locals to roll up their sleeves.

"Don't be scared, just have a go," he said.

"It doesn't take that much time to be able to save someone's life."

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