IEC 60335-2-91:1997 Safety of household and similar electrical appliances - Part 2-91: Particular requirements walk-behind and hand-held lawn trimmers and lawn edge trimmers
2008IEC 60335-2-91:2008 Household and Similar Electrical Appliances - Safety - Part 2-91: Particular Requirements for Walk-Behind and Hand-Held Lawn Trimmers and Lawn Edge Trimmers (Edition 3.0)
2002IEC 60335-2-91:2002 Household and similar electrical appliances - Safety - Part 2-91: Particular requirements for walk-behind and hand-held lawn trimmers and lawn edge trimmers
1997IEC 60335-2-91:1997 Safety of household and similar electrical appliances - Part 2-91: Particular requirements walk-behind and hand-held lawn trimmers and lawn edge trimmers