The document specifies safety requirements and their verifications for the design and construction of portable combustion-engined, hand-held chain-saws for tree service, designed for use by one operator. It is applicable to chain-saws with an engine displacement of maximum 40. These chain-saws are only intended to be used for tree service operation by an operator working up in trees. It describes methods for the eliminiation or reduction of hazards arising from their use. In addition it specifies the type of information on safe working practices to be provided by the manufacturer.