Mass. Gen. Laws ch. 94 § 316
The director may, in accordance with the provisions of chapter thirty A, adopt and amend regulations which require that each appliance in a class or subclass of appliances which is displayed for sale or for promotional purposes bear a label. The same regulations shall apply to each appliance in any subclass of appliances. The director may require said label to contain any or all of the following information, in such form as he may prescribe: (1) the cost in dollars or units of energy or both of operating the appliance during a year or any part of said year as determined under section three hundred and seventeen; (2) any numerical measure of efficiency which accurately reflects the relative efficiencies of all appliances within a class or subclass; and (3) a brief description of testing and computation procedures used to determine the above information.
The director shall prescribe the form of such labels and may establish procedures for their production, distribution and use, except that he may not require that any label be produced, distributed or affixed outside the commonwealth.
Mass. Gen. Laws ch. 94, § 316