Unit: Person Hour -- Links

Getty AAT: NA (closest match: Workers)

Merriam-Webster: Person-hour

See also Masters 2018 for modern calculations. (link)

Unit: Person Hour -- Description

Person-hours (also man-hour or effort-hour, abbraviated 'p-h') measure the time a task takes in terms of both time and individuals involved. As an example, a task which takes 50 p-h means that 10 people can complete the task in 5 hours or 5 people can complete the task in 10 hours.

For the sake of simplicity the algorithms used here assume a linear progression: that 50 p-h means that 2 people need 25 hours and 25 people need 2 hours to complete a task. In reality, the low and high ranges are not exactly linear, as one or two people are not as efficient as an 'ideal' group, and an overly large number also tends to be less efficient due to space limitations. None of the authors used in this study have investigated the efficiency for diverse numbers of workers, so the loss in terms of time for the high and low ranges of workers is unclear. The algorithms presented here assume the most efficient number of people for a given task.

I have chosen the term person-hour over the more common man-hour since some of the detailed records for pre-industrial labor show that some workforces were made up of a majority of women (e.g. Heimpel 2009).