Stop Sending Notification after specific time period

I am trying to figure this last part of my configuration out.

I want notifications to be sent after the 10 minute delay: Got that figured out.
I want notifications to be resent every ten minutes the host remains down: Got that figured out as well.
I want the notifications to stop after the host has been down for an hour because by that time, I know it’s down and don’t want to receive any more emails: This is the part I need help with.

How can I configure it to stop sending notifications after the host/service has been down for 1 hour???

Thanks in advance.
MH