This NFIRSGram explains how to document times for incidents that occur during a change to, or a change from, daylight saving time.
When the time changes from daylight saving time to standard time, and vice versa, a common question asked is, “How do I document times for incidents that occur during the time change?”
For instance, your department’s alarm time is 00:57:45, and you arrive on scene at 01:05:22. You are on the scene of the incident for approximately 56 minutes, and your last unit clears the scene at 02:01:11.
If you document the clear time as 01:01:11 after setting the time back an hour, you will receive a critical error message that the clear time is prior to the arrival time.
If you document the clear time as 03:01:11 after setting the time forward an hour, you indicate that you were on the scene an hour longer than you were.
The best course of action is to document any incident that occurs during the time change as if the time change did not occur.