The NFIRS specification provides this definition for Relational Edit Rule 183:
Relational Edit Rule 183 — If the Incident Type is not in the 800 series and the Last Unit Cleared Date/Time occurs 24 hours or more after the Alarm Date/Time then the system shall generate a warning message. This rule should take effect only after 1/1/2012. Warning Message: 'Incident duration of one day or more for a non severe weather or natural disaster incident. Please check incident times. If accurate, no further action required'