FOREWORD

1) The International Electrotechnical Commission (IEC) is a
worldwide organization for standardization comprising all national
electrotechnical committees (IEC National Committees). The object
of IEC is to promote international co-operation on all questions
concerning standardization in the electrical and electronic fields.
To this end and in addition to other activities, IEC publishes
International Standards, Technical Specifications, Technical
Reports, Publicly Available Specifications (PAS) and Guides
(hereafter referred to as "IEC Publication(s)"). Their preparation
is entrusted to technical committees; any IEC National Committee
interested in the subject dealt with may participate in this
preparatory work. International, governmental and nongovernmental
organizations liaising with the IEC also participate in this
preparation. IEC collaborates closely with the International
Organization for Standardization (ISO) in accordance with
conditions determined by agreement between the two
organizations.

2) The formal decisions or agreements of IEC on technical
matters express, as nearly as possible, an international consensus
of opinion on the relevant subjects since each technical committee
has representation from all interested IEC National Committees.

3) IEC Publications have the form of recommendations for
international use and are accepted by IEC National Committees in
that sense. While all reasonable efforts are made to ensure that
the technical content of IEC Publications is accurate, IEC cannot
be held responsible for the way in which they are used or for any
misinterpretation by any end user.

4) In order to promote international uniformity, IEC National
Committees undertake to apply IEC Publications transparently to the
maximum extent possible in their national and regional
publications. Any divergence between any IEC Publication and the
corresponding national or regional publication shall be clearly
indicated in the latter.

5) IEC itself does not provide any attestation of conformity.
Independent certification bodies provide conformity assessment
services and, in some areas, access to IEC marks of conformity. IEC
is not responsible for any services carried out by independent
certification bodies.

6) All users should ensure that they have the latest edition of
this publication.

7) No liability shall attach to IEC or its directors, employees,
servants or agents including individual experts and members of its
technical committees and IEC National Committees for any personal
injury, property damage or other damage of any nature whatsoever,
whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon,
this IEC Publication or any other IEC Publications.

8) Attention is drawn to the Normative references cited in this
publication. Use of the referenced publications is indispensable
for the correct application of this publication.

9) Attention is drawn to the possibility that some of the
elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or
all such patent rights.