This guide covers a methodological approach to developing protocols for collecting empirical building or facility energy performance data. The methodological approach covered in this guide is appropriate for commercial and institutional buildings or facilities, and with some adaptations, the approach can also be used for larger multifamily buildings or small industrial buildings or facilities. This guide does not specify a complete project or experimental design, the hardware or software needed for data collection and data management, or the data analysis techniques to be used. The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.