I suggest you decide what metric(s) you wish to use, and what purpose they are for and clearly define the boundaries of what you are measuring.
If you are trying to measure the efficiency of a machine. There are several measures used. One is utilisation, others just occupacity, manufacturing velocity, energy efficiency and another is OEE (Overall Equipment Effectiveness).
My personal preferance is to use OEE if the purpose of the metric is to increase output or improve reliability.
There are several sites on the web which detail this metric if you do a search on any of the search engines.
OEE is also used as a World Class Benchmarking metric, where World Class Batch plants have OEE's of > 85%. This metric takes into account all time, including downtime, maintenance, washes, changeovers, production, production speed and quality/defects, and so in my opinion is a comprehensive measure.
It is worth noting that this metric should not be used in isolation, but should be used with several other indicators.
You can use OEE for people but it is more complicated, and potentially political.