Mass. Gen. Laws ch. 94, § 305D

Each restaurant, having a seating capacity of twenty-five persons or more, shall have on its premises a device approved by the department of public health that is designed and intended for use in removing food which may become lodged in a person's throat or each such restaurant shall have on its premises, when food is being served, an employee trained in manual procedures approved by the department of public health to remove food so lodged in a person's throat. The department of public health shall adopt regulations listing all approved devices and manual procedures which it determines may be used effectively to remove food lodged in a person's throat. Each such restaurant shall make adequate provisions for insurance to cover employees trained in rendering such assistance. Any person, or employee of any person who, in good faith, volunteers to remove or attempts to remove such food in an emergency shall not be liable for any civil damages as a result of any acts or omissions by such person or employee in rendering such emergency assistance.