This document is applicable to portable ladders made only of non-conductive stiles, including accessories (pole leaning device, adjustable levelling device, adjustable ladder stabilizer, etc.) used to work on or near electrical systems and installations in the low voltage range (up to 1 000 V AC/1 500 V DC.). These ladders are used, to provide temporary access, generally on overhead line structures and to undertake electrical operations. They are intended to be used by one person only. These ladders, in conjunction with other protective equipment provide sufficient insulation level to protect against inadvertent contact with live low voltage installations. This document does not cover ladders used for live working on electrical installations at voltages above 1 000 V AC and above 1 500 V DC. These insulating ladders are separately covered by EN 61478. This document does not cover products not made entirely with non-conductive stiles generally called mixed ladders. In this case EN 131 series apply. This document does not cover step stools which are covered by EN 14183. These ladders are only for professional use. Only skill persons, after an appropriate training can use this type of ladder for professional applications. The products designed and manufactured according to this document contribute to the safety of the users provided they are used by skilled persons, in accordance with safe methods of work and the instructions for use (where appropriate).