ISO 11771:2010 specifies a generic method for the determination and the reporting of time-averaged mass emissions from a specific installation or of a family of installations (or common source type), using data collected by measurements, and by establishing: mass emission rates by the simultaneous measurement of concentration and gas flow, using standardized manual or automatic methods, and also the estimation of the uncertainty of the measurements; time-averaged mass emission rates using time series of mass emission rate values, their uncertainty characteristics, and also the determination of the expanded uncertainty of the average; time-averaged emission factors for a specific installation or of a family of installations and their associated uncertainty characteristics; a quality management system to assist the process of inventory quality assurance and verification.

ISO 11771:2010 is applicable to the determination of emission factors for stationary sources including emissions from industrial processes where calculation from fuel and raw material is not practical, for greenhouse gases, and air pollutants including fine particulate material. ISO 11771:2010 does not address compliance monitoring in the context of emission control regulations.

ISO 11771:2010 requires the use of measurement-based methods and calculation-based methods that use measurement data. It covers the planning and execution of the measurement programme to collect data, selection of sampling methods, calculation of results, estimation of uncertainty, determination of emission factors, and the reporting of information in a form that enables users to apply them. ISO 11771:2010 specifies how to: generate time-averaged mass emission rate data of a known quality, for a defined period of time, and a documented set of operational conditions; generate complete data sets representative of a known time period (i.e. a calendar year) by filling gaps in mass emission rate data series and combining data sets numerically; calculate emission factors for a known time period; calculate time-averaged emission factors of a known quality for a known source type.

The measurement of emissions from vehicular, area or fugitive sources is not specifically covered. However, ISO 11771:2010 can be used for quantification of emission factors for those sources provided that measurements of emissions are available.

ISO 11771:2010 does not explicitly include measurement procedures that are fully described in the referenced standards. Neither does it provide advice on the generation of activity statistics.

ISO 11771:2010 is compatible with ISO 14064-1 and ISO 14064-3.