Section R. 408.30536a - General requirementsRule 536a.
Sections E3402.2, E3405.2 and E3407.5 are amended to read as follows:
E3402.2. Penetrations of fire-resistance-rated assemblies. Electrical installations in hollow spaces, vertical shafts, and ventilation or air-handling ducts shall be made so that the possible spread of fire or products of combustion will not be substantially increased. Electrical penetrations through fire-resistance-rated walls, partitions, floors, or ceilings shall be protected by approved methods to maintain the fire-resistance-rating of the element penetrated. Penetrations of fire-resistance-rated walls shall be limited as specified in Section R302.4.E3405.2. Working clearances for energized equipment and panelboards. Except as otherwise specified in chapters 34 through 43, the dimension of the working space in the direction of access to panelboards and live parts likely to require examination, adjustment, servicing, or maintenance while energized shall be not less than 36 inches (914 mm) in depth. Distances shall be measured from the energized parts where such parts are exposed or from the enclosure front or opening where such parts are enclosed. In addition to the 36-inch dimension (914 mm), the work space shall not be less than 30 inches (762 mm) wide in front of the electrical equipment and not less than the width of such equipment. The work space shall be clear and shall extend from the floor or platform to a height of 6.5 feet (1 981 mm) or the height of the equipment, whichever is greater. In all cases, the work space shall allow at least a 90-degree (1.57 rad) opening of equipment doors or hinged panels. Equipment associated with the electrical installation located above or below the electrical equipment shall be permitted to extend not more than 6 inches (152 mm) beyond the front of the electrical equipment. [110.26(A)] Exception:
1. In existing dwelling units, service equipment, and panelboards that are not rated in excess of 200 amperes may be in spaces where the height of the working space is less than 6.5 feet (1 981 mm), but greater than 5 feet (1 524 mm). [110.26(A)(3) Exception 1 amended]2. Meters that are installed in meter sockets may extend beyond the other equipment. Meter sockets shall not be exempt from the requirements of this section. [110.26(A)(3) Exception 2] E3407.5. Polarity of connections. No grounded conductor shall be attached to any terminal or lead so as to reverse the designated polarity.Mich. Admin. Code R. 408.30536a