A method is provided for controlling the operating temperature of a catalytic reactor using a closed-loop system that provides for varying the reactor input and other operating parameters in order to maintain the operating temperature of the reactor at or near the initial setpoint temperature for operation of the reactor. The present invention is a protective screen guard having a screen element 12 with spaced apart flanged fasteners 14 for engaging the lip 16 of a lamp, heat lamp, or the like 18. The blades extend radially outwardly to the gage. In a preferred embodiment, the nitroxide antioxidant is Tempol. The driving motor is mounted in the tubal body, and the driving motor has a first and a second conductive parts. One alternate embodiment roof brush provides a hose attachment which permits cleaning solution to be discharged from the cleaning head at the bristles.