Mass. Gen. Laws ch. 148 § 26
Any basement of a mercantile establishment, any building used in whole or in part for the business of woodworking, or for the business of manufacturing or working upon wooden, basket, rattan or cane goods or articles, or tow, shavings, excelsior, oakum, rope, twine, string, thread, bagging, paper, paper stock, cardboard, rags, cotton or linen, or cotton or linen garments or goods, or rubber, feathers, paint, grease, soap, oil, varnish, petroleum, gasoline, kerosene, benzine, naphtha or other inflammable fluids or compounds, and any building used in whole or in part for the business of keeping or storing any such goods or articles except in such small quantities as are usual for domestic use or for use in connection with and as incident to some business other than such keeping or storing, shall, upon the order of the marshal, be equipped with automatic sprinklers; provided, that no such order shall apply to any building unless four or more persons live or are usually employed therein above the second floor.
Mass. Gen. Laws ch. 148, § 26