Is there a stated maximum allowable amount of recessed ceiling lights (unprotected openings) or aggregate maximum area permitted to a rated ceiling similar to that stated in 3.1.9.4. for outlet boxes. I assume the options are to either recess the light in a type X drywall box matching the ceiling rating or install a fire rated shroud if the unit itself doesn't come with a rating? I like the clarity to the wording of 3.1.9.4 to the NBC 2015. thanks.