Potable water rules require safe drinking water, proper marking, hygiene controls, and restricted use of shared cups. Employers in the specified workplaces must provide adequate clean, wholesome and safe drinking water that is readily accessible to all employees. Non-piped drinking water must be stored in properly marked vessels, replenished daily and protected from contamination, and common drinking tumblers are prohibited except where water is delivered by a rising jet. In building or other construction work, drinking water must be kept in closed containers with tap dispensing, transport and storage containers must be cleaned and disinfected regularly, and drinking water must not be connected to any supply unfit for drinking.