Toilets on construction sites
OSHA's construction sanitation standard sets a minimum number of toilet facilities by crew size: 1 for 20 or fewer employees; 1 toilet seat and 1 urinal per 40 workers for 20 or more; and 1 toilet seat and 1 urinal per 50 workers for 200 or more (OSHA 1926.51, Table D-1). The same standard requires adequate washing facilities near the worksite where crews handle paints, coatings, herbicides, insecticides, or other harmful contaminants.
Showers and lavatories in general industry
Where showers are required, OSHA's general industry standard calls for one shower for each 10 employees of each sex, or fraction of 10, who are required to shower during the same shift, with hot and cold water feeding a common discharge line. Each lavatory must have hot and cold running water, or tepid running water (OSHA 1910.141).
Sizing trailers to the crew
- 13 ft shower and restroom trailer: 3 private stalls, each with a shower and restroom.
- 22 ft trailer: 6 stalls. 30 ft trailer: 8 stalls.
- 20 ft shower container: 5 shower heads and 3 sinks where restrooms are already covered.
- Laundry trailers and sleeper containers when crews stay on site.
Every combination stall lists hot and cold water. Count people per shift, not total headcount, and confirm with your safety officer which OSHA standard covers your site.
Feeding the same crew
Long projects that need showers usually need meals too. A mobile kitchen trailer on the same delivery plan keeps crews fed on site, and CDC handwashing guidance is a reason to add a handwashing trailer near the dining area.