PDFWAC 480-66-490
Location and types of toilets.
(1) Movable facilities. Flush, chemical, or incinerator type toilets must be provided on the following movable facilities:
(a) The lead locomotive of all trains except when used in yard service.
(b) Baggage and express cars where employees are required to work en route.
(c) Cabooses.
(2) Stationary facilities. Appropriate toilets, as required by these rules, must be provided and made accessible to all employees at all terminals, yards, stations, depots, office work areas, engine houses and shops, bunk or section houses, section headquarters, lunch rooms, and maintenance of way camps.