Removing office lighting
Most likely a 3 phase system. Could be 120v or 347v/600v(not sure on u.s equivalent 277v/480v?). You really don't want to mess around with that stuff unless you've got all the power off. Turning switches off isn't going to cut it if they shared the neutrals. Being completely honest If you don't know what your doing with a 3 phase system or qualified to work on it you should be anywhere near it. You don't just get a tingle off those larger voltages, you get off clean if your real lucky, hospital if your a little lucky and you don't want to know what happens if your lucks all gone for the day.
And no your not allowed to work on it legally.
Sarcasm is my friend
I'm here to learn too, i do mostly commercial/industrial/new construction and this place is a great way to pick up tips on residential from some good electrical minds. Excuse the spelling, my phone has a mind of it's own.