Hi Vilas,
I understand there is no problem of testing it while it's running. But the way it's written, it assumes you arrive at the aircraft with APU off which is never the case in the company I work for. I understand the check must be done for the first flight of the day. Some people will argue that you can't assume maintenance did the check... Well, we trust them to maintain our aircraft airworthy; I think we can trust them to have done a simple no brainer task as an APU fire test 1h before the crew arrive at the aircraft. Or maybe all the pilots working in my company are foolish. lol
