This SAE Recommended Practice specifies a uniform procedure forthe evaluation of gaseous exhaust emissions from small utilityengines typically less than 20 kW. Details of engine test setup andexhaust gas analysis techniques are specified with the intent ofproviding a uniform and reproducible method of measurement.

The intent has been to allow as much flexibility as possible inthe physical construction of the experimental apparatus. Therefore,only those portions of the apparatus whose operation is critical tothe accurate measurement of emissions levels are prescribed indetail.

An engine test procedure including a test sequence is outlinedsuch that it would cover the various applications in which smallengines are used. The intent is to provide an understanding of thelevels of exhaust emissions and does not imply that in givenapplication, an engine would operate in all the modes outlined inthe test procedure.

This document is intended as a guide toward standard practiceand is subject to change to keep pace with experience and technicaladvances.