The department or its duly authorized agents shall from time to time perform inspections and testing of the premises of a property to determine the level at which it is contaminated with radon gas or radon progeny as a spot-check of the validity of measurements or the adequacy of abatement measures performed by persons certified or credentialed under section 136B.1. Following testing the department shall provide the owner of the property with a written report of its results including the concentration of radon gas or radon progeny contamination present, an interpretation of the results, and recommendation of appropriate action. A person certified or credentialed under section 136B.1 shall also be advised of the department’s results, discrepancies revealed by the spot-check, actions required of the person, and actions the department intends to take with respect to the person’s continued certification or credentialing.