When I was working, I ran up to the place in the morning, quickly drank the drink (they only give you 5 minutes to drink it anyway) ran back to work, waited the hour, dashed back and gave blood. So it wasn't too difficult to get out of work, just took about half an hour all up - and I just worked through half my lunch break instead.

I am at risk I suppose because i'm overweight, but I was basically a "normal" weight for my first two pregnancies and still had the test because sometimes people can get it that aren't at risk, and I would rather know than not know