A. The proper attachment of a standard quality filter designed and recommended for the machine, device or apparatus of the kind, condition, and manufacture in question; and, also

B. The repair and adjustment of motors, when necessary, so that commutators and brushes operate efficiently and cause no needless electrical interference; and

C. If, after the proper attachment of such a filter, any diathermy or high frequency violet ray apparatus still produces severe interference with radio reception, then reasonably preventable electrical interference with radio reception shall be understood to be interference that can be minimized or eliminated by the complete screening of such apparatus with a galvanized or copper wire screen, properly grounded, and of sufficient dimensions to enclose not only the apparatus but also at the same time the patient being treated.