Military times
Conventional forms of time are preferred by the AMA. If military (or 24-hour clock) time is dictated, do not convert to conventional time.
The military operates off a 24-hour clock, beginning at midnight (which is 0000 hours). So, 1:00 AM is 0100 hours, 2:00 AM is 0200 hours, and so-on up until 11:00 PM which is 2300 hours.
The question sometimes arises whether midnight is written as 2400 or 0000. Military and emergency services personnel refer to midnight both ways. However, digital watches and clocks that display time in a 24-hour format and computer equipment treat midnight as the start of a new day and express it as 0000.
Do not use a.m. or p.m.
Do not insert a colon between the hours and the minutes.
The word hours should be inserted for clarity, even if not dictated.
Anesthesia began at 1300 hours.
Surgical procedure ended at 0845 hours.
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