Final answer:
A not observed report (NOB eval) is meant for short duties or temporary assignments not exceeding 3 months.
Step-by-step explanation:
A not observed report (NOB eval) is submitted for short periods of duty or temporary duty not to exceed 3 months.
This means that if a duty period or temporary assignment is 3 months or shorter, an NOB eval can be used as the evaluation report.
However, if the duty exceeds this time frame, a more comprehensive evaluation would be necessary.