Charging for unearned hometime??? Driver late and I'm getting charged.

A driver is good within 382 like you posted. 392.5 however, is a bit more restrictive. That is where the "Under the influence" wording comes from. So yes, the driver has to be sober (not under the influence), then wait 4 hours
Here is the regs from eCFR — Code of Federal Regulations

§392.5 Alcohol prohibition.
(a) No driver shall—

(1) Use alcohol, as defined in §382.107 of this subchapter, or be under the influence of alcohol, within 4 hours before going on duty or operating, or having physical control of, a commercial motor vehicle; or

 

4 hours or not. Who is going to check that and how? Are you legally drunk or not when you drive is what matters.

That's to say, that usually when I drink, I need more than 4 hours after.

 

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Geeze man, you're asking for it big time! 4 hours and regs are not the issue here at all. He's irresponsible so one solid stern warning ( if you're feeling generous ) and gone on the next or just gone now.

Personally I wouldn't give one at all. I'm a tanker hand myself. Love to drink beer and hit the honky tonk all I can BUT my personal rule was I didn't go near a CMV for 12 hours from my last drink. I ddin't care who was calling or running out of XYZ chemical. 12 hours, no exceptions.

Way too many unknowns here, things you will learn about the hard way. You have no chance especially if he kills or cripples somebody......and if your insurance carrier finds out you knew about this......they don't have to pay.

I say clean up now before it's too late.

JMO