Worksite Toilet and Handwash Count

Details, formula, and sources

ScopeA recovery site fills with crews faster than it fills with portable toilets, and the federal minimum comes from three different OSHA tables depending on the work. Demolition and debris removal is construction, under 29 CFR 1926.51 Table D-1; a warehouse running relief supplies is general industry, under 1910.141 Table J-1; a crew clearing storm-damaged orchards is agriculture, under 1928.110. The same 45 workers need 2 seats and 2 urinals, 3 water closets, or 3 toilets and 3 handwashing stations. A debris contractor with 85 workers needs 3 toilet seats and 3 urinals at one per 40. Table D-1 has two quirks the calculator reports rather than smooths: its rows overlap at exactly 20 workers, where the larger reading is shown, and it steps down at 200, where 199 workers need 5 and 5 but 200 need 4 and 4 at one per 50 -- a site at the line should not read the drop as permission to remove units. A relief warehouse with 230 employees needs 8 water closets; where the rooms will not be used by women urinals may replace some, but water closets cannot fall below two-thirds of the minimum, so 6 plus 2 urinals. Field agriculture needs 1 toilet and 1 handwashing facility per 20 employees within a quarter-mile walk, applies only where 11 or more do hand labor in the field, and exempts field work of 3 hours or less including travel. Handwashing is required under all three rules but counted only by the agricultural one. These are minimums; heat and shift overlap justify more. It does not apply the building code, the labor camp standard, or shelter standards, or set service intervals. The OSHA standards, the state plan, and the competent person govern.

Formula or tableconstruction (1926.51 Table D-1): under 20 -> 1; 20 to 199 -> ceil(n/40) seats + ceil(n/40) urinals; 200 or more -> ceil(n/50) each. General industry (1910.141 Table J-1): 1-15 1, 16-35 2, 36-55 3, 56-80 4, 81-110 5, 111-150 6, over 150 6 + ceil((n-150)/40); urinals may replace water closets where not used by women down to ceil(2/3 x minimum). Agriculture (1928.110): ceil(n/20) toilets and handwashing facilities where 11 or more do field hand labor.

Source and edition29 CFR 1926.51(c)(1) Table D-1, 29 CFR 1910.141(c)(1)(i) Table J-1 and footnote 1, and 29 CFR 1928.110(a) and (c)(2), read at law.cornell.edu on 2026-09-30 and reproduced as federal regulation. OSHA and the state plan govern.

Free accessThe Code of Federal Regulations is public domain; Tables D-1 and J-1 and the 1928.110 ratio are transcribed in full and were checked against the Cornell LII copies.

What governsMath aid for personal verification. Stop work and consult the qualified person on site if any number does not match the field condition.

• Construction rows overlap at 20 the per-40 row's 1 seat and 1 urinal is shown at exactly 20, the larger reading29 CFR 1926.51 Table D-1
• Two-thirds floor water closets not below ceil(2/3 x table minimum) when urinals substitute29 CFR 1910.141 Table J-1 footnote 1
• Agricultural scope 11 or more field hand laborers on a given day; field work of 3 hours or less exempt29 CFR 1928.110(a), (c)(2)(v)