We are an installer of temp. control systems and have just been questioned regarding a present installation practice of the controls for a air handling unit and the associated speed drive. We needed to install conduit from our control panel to the other end of the unit for the speed drive and along the way various control devices. To support the conduit we utilitized beam clamps and a small length of strut from the standing seams of the ductwork. I know that this is standard practice for many years in the industry however I would like to know what section of the code would cover this practice.