Every device monitored by Red Alert has a checking interval. The default checking interval is 15 minutes. That is, by default, a device is checked for problems once during every 15 minute period.
You may choose to triple the frequency at which Red Alert checks a particular device, by activating 5-Minute Monitoring, which is an Enhanced Service. A device with this service activated has a checking interval of 5 minutes. That is, Red Alert checks it for problems once during every 5 minute period.
Whenever you add or edit a monitored device, you are given an opportunity to choose its checking interval.
Note: The only Notification Persistence option available for devices with 5-Minute Monitoring is "Up to twice & when OK again". Therefore, if you change a device's checking interval from 15 minutes to 5 minutes, all of the device's Persistence settings will automatically be changed to that option. A warning about this appears in the relevant section of the device editing form.