can one delay alert during specific hours?

Pardon me if this is answered somewhere. 

Occasionally we have servers that miss a ping at night - probably due to backups going over production network (there are a few). I want to not get emailed on the first bad ping - be really bad before you wake me up - say between midnight and 6am. But it is not DOWNTIME as in never tell me. Can I do this? Can I say delayed red between specific hours. For now I just delayed the whole thing.


Thanks

Bakkies