While there is no formal policy in place in my Department in relation to the donation of blood by staff during normal working hours, I can confirm to the Deputy that staff who wish to donate blood during normal working hours are facilitated. For health and safety purposes, staff members on the flexitime system must clock out on leaving my Department's buildings. However, those leaving to donate blood can claim back the time it takes (of the order of 1-2 hours generally) to make the donation.
While my Department has facilitated group donations by staff in the past, and maintains a positive approach in this regard, it has no specific measures in place to encourage the donation of blood as the issue is considered to be essentially a matter for personal decision by individual staff members.