Section 2.947 - Measurement procedure(a) Test data must be measured in accordance with the following standards or measurement procedures:(1) Those set forth in bulletins or reports prepared by the Commission's Office of Engineering and Technology. These will be issued as required, and specified in the particular part of the rules where applicable.(2) Those acceptable to the Commission and published by national engineering societies such as the Electronic Industries Association, the Institute of Electrical and Electronic Engineers, Inc., and the American National Standards Institute.(3) Any measurement procedure acceptable to the Commission may be used to prepare data demonstrating compliance with the requirements of this chapter. Advisory information regarding measurement procedures can be found in the Commission's Knowledge Database, which is available at www.fcc.gov/labhelp.(b) Information submitted pursuant to paragraph (a) of this section shall completely identify the specific standard or measurement procedure used.(c) In the case of equipment requiring measurement procedures not specified in the references set forth in paragraphs (a)(1) through (3) of this section, the applicant shall submit a detailed description of the measurement procedures actually used.(d) A listing of the test equipment used shall be submitted.(e) If deemed necessary, additional information may be required concerning the measurement procedures employed in obtaining the data submitted for equipment authorization purposes.(f) A composite system is a system that incorporates different devices contained either in a single enclosure or in separate enclosures connected by wire or cable. If the individual devices in a composite system are subject to different technical standards, each such device must comply with its specific standards. In no event may the measured emissions of the composite system exceed the highest level permitted for an individual component. Testing for compliance with the different standards shall be performed with all of the devices in the system functioning. If the composite system incorporates more than one antenna or other radiating source and these radiating sources are designed to emit at the same time, measurements of conducted and radiated emissions shall be performed with all radiating sources that are to be employed emitting.(g) For each technical requirement in this chapter, the test report shall provide adequate test data to demonstrate compliance for the requirement, or in absence of test data, justification acceptable to the Commission as to why test data is not required.42 FR 44987, Sept. 8, 1977, as amended at 44 FR 39181, July 5, 1979; 51 FR 12616, Apr. 14, 1986; 80 FR 33442 , June 12, 2015; 82 FR 50828 , Nov. 2, 2017