- Distribution or shipping centre, mean floor area
- 47,800 sq ftAgainst 12,900 for a building the survey classes simply as a warehouse. From the 2018 Commercial Buildings Energy Consumption Survey, Table B15, carrying a relative standard error of 12.78 percent.
- On medians, the gap widens
- 14,000 vs 5,100 sq ftTable B16 of the same survey. The mean is pulled by a small number of very large buildings; the median is the one that describes the building you are probably standing in.
- Square feet per worker
- 2,004 vs 2,222Distribution centres are marginally denser than plain warehouses. Worth noting the basis: the survey counts main-shift workers, which is the same basis OSHA uses for sanitation at 1910.141(a)(2). Those two chain together later on this page and the chain only works because the basis matches.
- Weekly operating hours
- Mean 57, median 50Against 46 and 44 for plain warehouses. Refrigerated warehouses report a mean of 101, printed here with its 44.65 percent relative standard error on building count and treated as indicative only. The building type with a 168-hour median is self storage, not distribution.
- What that hours figure leaves out
- The cleaning window, by definitionThis is the hinge. The survey's own terminology excludes from weekly operating hours the “hours when the building is occupied only by maintenance, housekeeping, security, or other support personnel.” The federal definition of a warehouse's operating hours is drawn around the window this work happens in. Subtracting 57 from 168 is arithmetic on a mean, not a measured quantity, and it is offered as arithmetic.
- Employees per establishment, nationally
- 75.8 in general warehousingCounty Business Patterns 2022, the national by-industry cut and not a county figure: NAICS 493110 averages 75.8 employees across 15,416 establishments, against 15.6 for sector 423 and 18.9 for 424. But a third of general-warehousing establishments have four employees or fewer, so “warehouse” is not a synonym for “huge,” and a scope written for one is wrong for the other.