The Irish Blood Transfusion Service (IBTS) is introducing an appointment system for its blood donation clinics during the coronavirus pandemic.
It says it needs to maintain its supply but is introducing changes in order to implement safe social distancing.
People intending to donate should make contact with the service in advance.
They will then be screened as they arrive and if they are well they will go through the normal process, said Andy Kelly, Chief Executive of the IBTS.
"We have hand sanitisers in lots of places around the clinic venues and we have distance between people and beds.
"We will have a much more controlled number of people in our clinics."
Cancer patients, trauma cases and newborn babies will still require transfusions.
However, Mr Kelly says only 80% of the normal supply is required due to the cancellation of many hospital procedures and surgeries.
"Some surgery will have to go on because of urgent cases, cancer treatments will continue, there will be some trauma but less than normal.
"There will be some transplant cases that continue and support for those people awaiting transplant.
"There will be premature babies who may require blood when they are born and maybe their mothers as well.
"So, all of those things and there are a number of patients who are transfusion-dependent who will require transfusion on a regular basis who absolutely have to get them."
There has been a drop of 13% in the number of people attending which the IBTS says is manageable for now.