Surface-mounted luminaires with a ballast shall have a minimum clearance of _____ in. from combustible low-density cellulose fiberboard, unless the luminaire is marked for surface mounting on combustible low-density cellulose fiberboard.
c) 1 ½
See answer and applicable Code reference
The correct answer is: c) 1 ½
Article 410 covers luminaires, lampholders, and lamps. Part XII of this Article covers the special provisions for electric-discharge lighting systems of 1,000V or less. As per 410.136(B), "Where a surface-mounted luminaire containing a ballast, transformer, LED driver, or power supply is to be installed on combustible low-density cellulose fiberboard, it shall be marked for this condition or shall be spaced not less than 1 ½ in. from the surface of the fiberboard. Where such luminaires are partially or wholly recessed, the provisions of 410.110 through 410.122 shall apply."