One average reduces different runs to one number; it does not show monitoring coverage, so it cannot stand as the full report.
Limit of the average
An average combines available samples. A brief rise and a long rise may contribute to the same average; a recording gap contributes nothing.
Conditions for comparison
Compare months calculated with the same scope and definition. Otherwise, a difference may reflect a change in runs or hours monitored as well as temperature.
Report lines
- Planned and covered monitoring hours.
- Runs with no file and unexplained gaps.
- Measured range and duration summary for available data.
- Monthly average and its denominator.
Measurement coverage
For example, if the plan calls for 100 monitoring hours and files cover 80, the average summarizes only available data. Temperature for the other 20 hours is unknown; compliance cannot be inferred.
Reading monthly change
Check planned and covered hours across months. If denominator or run mix changed, compare matched coverage before attributing a difference to temperature.
Excursion duration and event definitions depend on product specifications and the authorized quality process; an average does not decide them.
