ISO 11806-2:2011 gives safety requirements and measures for their verification for the design and construction of portable, hand-held, powered brush-cutters and grass-trimmers with a back-pack-mounted combustion engine power source and mechanical power transmission between the power source and the cutting attachment. Methods for the elimination or reduction of hazards arising from the use of these machines and the type of information on safe working practices to be provided by the manufacturer are specified.ISO 11806-2:2011 is not applicable to lawn-edge trimmers or to brush-cutters equipped with metallic blades consisting of more than one part, e.g. pivoting chain.ISO 11806-2:2011, taken together with the relevant clauses of ISO 11806-1, deals with all significant hazards, hazardous situations and hazardous events, with the exception of whole-body vibration from the back-pack power unit, relevant to these machines when they are used as intended and under conditions of misuse which are reasonably foreseeable by the manufacturer.