Good question, actually. You are pretty much free to handle guns as you see fit in your own home - CC without a permit, etc., as long as you aren't threatening anyone unduly. Not so lax at a place of business, though. You either have to OC at work, or leave a gun out in plain view, or get a permit to CC. Your employer likewise has to approve of you going armed (the trespassing thing can be applied to the help if they don't like it). Having a loaded handgun on a shelf under the counter makes it a concealed weapon ready at hand, and you can be charged for CCW violation (a 4th degree felony here - not trivial). I daresay that I've become something of an authority on the Ohio CCW laws in recent months, but it won't hurt my feelings if you want to consult an attorney as well.
In the meantime, you can scroll through the actual text of the relevant sections of the Ohio Revised Code to claify your particular situation: http://codes.ohio.gov/orc/2923.