Requests for donated blood have fallen 15% over the past three years, blood bank organisation Sanquin says on Tuesday.

The fall is due to a more efficient use of blood in hospitals and the introduction of operation procedures which reduce the need for blood transfusions, Sanquin says.

Because of the decline in use, Sanquin is closing 26 small donation locations and will send donors to large locations in the same area.

Blood and plasma donors remain essential to the health system, even though they may not be called on so often, says Sanquin.