scope:

General

National differences from the text of the International Electrotechnical Commission (IEC) Publication 60950-1, Information Technology Equipment - Safety - Part 1: General Requirements, Copyright 2005, are indicated by the following margin notations:

There are six types of national differences, as noted below. The national difference type is noted in the margin next to the affected text. The standard may not include all types of these national differences.

D1 - national differences based on national regulatory requirements which result in equivalent or more stringent requirements than in IEC 60950-1.

D2 - national differences based on other than national regulatory requirements which result in equivalent or more stringent requirements than in IEC 60950-1. DI - national differences based on IEC final draft international standards (FDIS).

DI national differences may be less stringent than, equivalent to, or more stringent than requirements in IEC 60950-1. DC - national differences based on UL and CSA component requirements.

DC national differences may be less stringent than, equivalent to, or more stringent than component requirements in IEC 60950-1.

D3 - national differences based on bi-national requirements which result in less stringent requirements than in IEC 60950-1.

DE - editorial national differences that correct typographical errors in IEC 60950-1 or revise the terminology, but do not alter the technical intent of the requirements. This notation is also used for informative statements such as the Preface.

National differences have been incorporated into the body of the standard. If national differences necessitate the deletion of IEC 60950-1 text, the IEC 60950-1 text has been retained but has been Except for tables and figures and annexes, text added as a result of national differences has been underlined. Text added as the Preface is not underlined.

A number of additional annexes are included at the back of the standard as national differences. Pointers to these annexes are provided in the right-hand margin of the body of the standard to direct the user to these informative/normative annexes. The pointer text is provided in BOLD ITALICS. Examples of such pointers are shown here in the right-hand margin.