A woman who has given blood 50 times in 30 years was sent home from a donor session after being told a hygiene ruling meant nurses could not touch her skin.
Sarah Midwinter, who said she has narrow veins, previously had nurses "tap" her skin to bring the vein to the surface, but nurses told her they were no longer allowed to use the method due to an infection danger, with new guidelines stating that the skin cannot be touched once it has been cleaned.
New guidelines state that the skin cannot be touched once it has been cleaned. Skin tapping is a common procedure to bring veins to the surface before a needle is inserted, but it has been banned in non-clinical environments.
As a result the 53-year-old was told she had to leave the donor session set up at her local church.
The NHS Blood and Transplant health authority said the safety of donors and the patients receiving blood was of "paramount" importance. It added because many donation sessions are in public venues they must observe "very stringent" rules on hygiene. But, Ms Midwinter, from near South Molton in Devon, said the ruling risks putting people off giving blood at a time when the NHS is appealing for new donors.
She said: "It makes me very cross. I've given blood all my life on and off and it's never been a problem. They will be turning people away, there must be lots of people with arms like mine ... it's completely ridiculous.
"They are making a hole in your arm anyway so presumably there is a slight risk of infection, but I wouldn't have thought having a finger on the arm was a huge risk factor. It seems ridiculous when the NHS is always appealing for new donors."
Ms Midwinter, who has the universal O Negative blood type, pleaded with nurses at the South Molton Methodist Church to let her donate, offering to either tap her arm herself or signing a waiver to allow the nurse to do it for her.
Ms Midwinter said the nurse told her she was allowed to tap on the arm, but once she took her finger away to swab the area and get the needle, the vein would go back down and she would be unable to see it. She was also told the nurses were unable to use rubber gloves. Ms Midwinter said the incident happened over a year ago, but when she was phoned more recently to come to the next session she asked if the ruling had changed and was told it was still in place.
Jo Tossell, NHS Blood and Transplant's director of infection prevention and control, said: "We are incredibly grateful to all our donors and we want them to give blood whenever they can. However, we have to observe very stringent rules on hygiene in order to ensure both the safety of our donors and the safety of those who receive blood."