Section 18.115 - Elimination and investigation of harmful interference(a) The operator of ISM equipment that causes harmful interference to radio services shall promptly take appropriate measures to correct the problem.(b) If the operator of ISM equipment is notified by the Commission's Regional Director that operation of such equipment is endangering the functioning of a radionavigation or safety service, the operator shall immediately cease operating the equipment. Operation may be resumed on a temporary basis only for the purpose of eliminating the harmful interference. Operation may be resumed on a regular basis only after the harmful interference has been eliminated and approval from the Regional Director obtained.(c) When notified by the Regional Director that a particular installation is causing harmful interference, the operator or manufacturer shall arrange for an engineer skilled in techniques of interference measurement and control to make an investigation to ensure that the harmful interference has been eliminated. The Regional Director may require the engineer making the investigation to furnish proof of his or her qualifications.50 FR 36067, Sept. 5, 1985, as amended at 80 FR 53750, Sept. 8, 2015