Alert Limits

You can enable alert limits to limit the number of alerts you receive over the course of a day.

This is different from recurring alerts, as the alert limits will apply to all definitions/events (i.e. not responding, low disk space, dead mail, etc.).

Go to Alerts -> Alert Settings.
Select the checkbox () next to Enable Alert Limits (if not already selected).
Enter a value for Maximum Alerts per Definition (the maximum number of alerts for each alerting event).
Enter a value for the Maximum Alerts per Day (the maximum number of alerts per day).

If you select Until Cleared, you will continuously be notified until the issue is resolved.
Click OK to save the changes.