Donating blood is probably the easiest, most tangibly beneficial forms of community service there is. As yet, no one has been able to produce artificial blood that is able to carry oxygen (which is the whole point of blood) so blood from donors is the only option.
Until the early 1990s, blood donation in New Zealand was somewhat haphazard, with different areas managing blood donations for themselves. To help with this, the NZBS (New Zealand Blood Service) was set up to manage blood donations nationally.
There have been a lot of changes in the last two decades. It used to be that blood donation services would take blood from anyone who had turned up (and was healthy). This led to blood being wasted. Red cell components last for 35 days, and platelets for just 5 days, before they become useless, so if blood of a particular blood type wasn’t needed – and needed quickly – then blood might have to be thrown away.
Things have changed.
Now the NZBS tracks the people who have made appointments to donate and the blood stock levels available. They also estimate the number of people who will donate without an appointment, and the number of people who will cancel their appointments. They do this several times a week to try and work out what blood types will probably be required over the next fortnight. Call centres then contact previous donors with the right blood type to try and make sure there is enough blood available for patients.