IEC 60335-1 deals with the safety of electrical appliances for household and similar purposes, their rated voltage being not more than 250 V for single-phase appliances and 480 V for other appliances. Battery-operated appliances and other d.c. supplied appliances are within the scope of this standard. Appliances not intended for normal household use but which nevertheless may be a source of danger to the public, such as appliances intended to be used by laymen in shops, in light industry and on farms, are within the scope of this standard. Examples of such appliances are catering equipment, cleaning appliances for commercial use, and appliances for hairdressers. The principal changes in this edition as compared with the fourth edition are as follows: - updated the text of the standard to align with the most recent editions of the dated normative references; - modified the functional safety requirements using programmable electronic circuits including software validation requirements; - updated Clause 29 to cover insulation requirements subjected to high frequency voltages as in switch mode power supply circuits; - updated Subclause 30.2 to further align the pre-selection option with the end-product test option; - deleted some notes and converted many other notes to normative text; - clarified requirements for class III constructions.