Section 62. The commissioner shall cause a system of elevator inspection to be instituted and maintained in the commonwealth. The commissioner shall assign an adequate number of competent inspectors for all elevators in the commonwealth. The commissioner shall have supervision of the installation, alteration, maintenance, inspection and approval of all elevators and shall enforce the regulations of the board of elevator regulations. No elevator shall be installed or altered until a copy of the plans and specifications of such elevator or of the proposed alterations shall have been filed by the owner of the premises where such elevator is to be installed or altered, or by the manufacturer of such elevator, and a certificate of approval or a specification of requirements shall have been issued by the commissioner. The word ''elevator'' shall include moving stairways, dumbwaiters, moving walks, material lifts and dumbwaiters with automatic transfer devices, wheelchair lifts, automatic people movers and other associated devices, except stair lifts located and installed in residential homes, that are commonly included within the elevator industry.