How much is your freetime worth?

My manager asked me the other day about a new service that we want to offer customers. Our service department wants to have a 24/7 emergency line. That means that one service technician would have the "emergency" phone on them at all times during their assigned week. They would need to answer all calls and be ready to run to the shop to get tools to go to a customer site at a moment's notice.

Right now my manager is offering an automatic 4.5 hours of overtime per week. That is for doing absolutely nothing. If nobody calls I get 4.5 hours of OT added to my check no matter what.

BUT

I can't do anything during that week. No drinking, no working on my car. Or anything else that would leave me without transportation, incapacitated, or out of phone contact for that week.

I also have a problem because there are only 3 service guys. 2 of which have families. Guess who is the only single guy? Yep, me.

I'm guessing that because of that I will be "encouraged" to either help out the other two guys or to do twice the amount of duty. Me taking two weeks a month and the other two guys taking one week.

All for $92 per week. (4.5 hours of OT minus 30% for taxes.)

That isn't much incentive. In theory it's an extra $2392 a year which is the equivalent of a $1.15 per hour raise. But is it worth the hassle?