Mass. Gen. Laws ch. 149 § 137
The proprietor of every foundry engaged in the casting of iron, brass, steel or other metal, and employing ten or more persons, shall establish and maintain, except in towns where it would be impracticable by reason of the absence of public or private sewerage or of any running water system, a toilet room of suitable size and condition for such persons to change their clothes therein, and provided with wash bowls, sinks or other suitable set appliances connected with running hot and cold water, and also a water closet connected with running water and separated from the said toilet room. The said water closet and toilet room shall be connected directly with the foundry building, properly heated, ventilated and protected, so far as may be reasonably practicable, from the dust of the foundry. Whoever fails to comply with this section after being requested so to do by an inspector shall be punished by a fine of not more than fifty dollars.
Mass. Gen. Laws ch. 149, § 137