I worked in bloodbanking for a career, there's also a fine line for marketing, I seem to remember there was an issue if we advertised a shortage if the word critical was used or not. During 9-11 so many people showed up to donate at one point all of the walk ins were full, and they were storing units on ice in picnic coolers in hallways, had to start turning away any type but O because there was so much they were just throwing it away, but blood has a forty day shelf life, and four months later they were having a shortage again. Blood pleas are typical during the holidays, regular donors are a very small portion of the population, and they might go in vacation, or just be too busy. We kept every one who had ever donated in a database, and could sort them by type because it was on file, and then mass mail, or call anyone in the community with the type we were low on.

I worked in bloodbanking for a career, there's also a fine line for marketing, I seem to remember there was an issue if we advertised a shortage if the word critical was used or not. During 9-11 so many people showed up to donate at one point all of the walk ins were full, and they were storing units on ice in picnic coolers in hallways, had to start turning away any type but O because there was so much they were just throwing it away, but blood has a forty day shelf life, and four months later they were having a shortage again. Blood pleas are typical during the holidays, regular donors are a very small portion of the population, and they might go in vacation, or just be too busy. We kept every one who had ever donated in a database, and could sort them by type because it was on file, and them mass mail, or call anyone in the community with the type we were low on.