This International Standard specifies a noise test code for determining, efficiently and under standardized conditions, the noise emission characteristics of portable, hand-held, internal combustion-engine-powered forest machines such as chain-saws, brush-cutters and grass-trimmers. Noise emission characteristics include the A-weighted emission sound pressure level at the operator position and the A-weighted sound power level. The code is applicable for manufacturers' product controls as well as type tests. It is intended that the results obtained will be able to be used to compare different machines or different models of the same type of machine. Although the noise emission values determined are obtained in an artificial operation, they are representative of noise emission in a real work situation.