IEC 60335-2-88:2002

INTERNATIONAL IEC
STANDARD
60335-2-88
Second edition
2002-10
Household and similar electrical appliances –
Safety –
Part 2-88:
Particular requirements for humidifiers intended
for use with heating, ventilation, or air-
conditioning systems
Appareils électrodomestiques et analogues –
Sécurité –
Partie 2-88:
Règles particulières pour les humidificateurs destinés
à être utilisés avec des appareils de chauffage,
de ventilation ou de conditionnement d'air
Reference number
Publication numbering
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INTERNATIONAL IEC
STANDARD
60335-2-88
Second edition
2002-10
Household and similar electrical appliances –
Safety –
Part 2-88:
Particular requirements for humidifiers intended
for use with heating, ventilation, or air-
conditioning systems
Appareils électrodomestiques et analogues –
Sécurité –
Partie 2-88:
Règles particulières pour les humidificateurs destinés
à être utilisés avec des appareils de chauffage,
de ventilation ou de conditionnement d'air
 IEC 2002  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch  Web: www.iec.ch
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R
International Electrotechnical Commission
Международная Электротехническая Комиссия
For price, see current catalogue

– 2 – 60335-2-88  IEC:2002(E)
CONTENTS
FOREWORD . 4
INTRODUCTION .6
1 Scope . 7
2 Normative references. 7
3 Definitions . 8
4 General requirement . 8
5 General conditions for the tests . 8
6 Classification . 8
7 Marking and instructions . 8
8 Protection against access to live parts . 9
9 Starting of motor-operated appliances . 9
10 Power input and current.10
11 Heating.10
12 Void .10
13 Leakage current and electric strength at operating temperature .10
14 Transient overvoltages.10
15 Moisture resistance.10
16 Leakage current and electric strength .11
17 Overload protection of transformers and associated circuits.11
18 Endurance .11
19 Abnormal operation.11
20 Stability and mechanical hazards.11
21 Mechanical strength.11
22 Construction .12
23 Internal wiring.13
24 Components .13
25 Supply connection and external flexible cords.13
26 Terminals for external conductors .13
27 Provision for earthing.14
28 Screws and connections .14
29 Clearances, creepage distances and solid insulation .14
30 Resistance to heat and fire .14
31 Resistance to rusting .14
32 Radiation, toxicity and similar hazards .14
Annexes.15
Annex AA (normative) Gaskets.15
Annex BB (normative) Test for liquid-containers.17
Bibliography.18

60335-2-88  IEC:2002(E) – 3 –
Table AA.1 – Physical properties of gasket materials .15
Table AA.2 – Accelerated aging conditions .16
Table BB.1 – Oven conditioning temperatures.17

– 4 – 60335-2-88  IEC:2002(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-88: Particular requirements for humidifiers intended for use
with heating, ventilation, or air-conditioning systems
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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 non-governmental organizations liaising
with the IEC also participate in this preparation. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
This part of International Standard IEC 60335 has been prepared by subcommittee 61D:
Appliances for air-conditioning for household and similar purposes, of IEC technical
committee 61: Safety of household and similar electrical appliances.
This second edition cancels and replaces the first edition published in 1997. It constitutes a
technical revision.
The text of this part of IEC 60335 is based on the following documents:
FDIS Report on voting
61D/117/FDIS 61D/122/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This part 2 is to be used in conjunction with the latest edition of IEC 60335-1 and its
amendments. It was established on the basis of the fourth edition (2001) of that standard.
NOTE 1 When “Part 1” is mentioned in this standard, it refers to IEC 60335-1.
This part 2 supplements or modifies the corresponding clauses in IEC 60335-1, so as to
convert that publication into the IEC standard: Safety requirements for electric humidifiers
intended for use with heating, ventilation, or air-conditioning systems.

60335-2-88  IEC:2002(E) – 5 –
When a particular subclause of Part 1 is not mentioned in this part 2, that subclause applies
as far as is reasonable. When this standard states "addition", "modification" or "replacement",
the relevant text in Part 1 is to be adapted accordingly.
NOTE 2 The following numbering system is used:
– subclauses, tables and figures that are numbered starting from 101 are additional to those in Part 1;
– unless notes are in a new subclause or involve notes in Part 1, they are numbered starting from 101, including
those in a replaced clause or subclause;
– additional annexes are lettered AA, BB, etc.
NOTE 3 The following print types are used:
– requirements: in roman type;
– test specifications: in italic type;
– notes: in small roman type.
Words in bold in the text are defined in Clause 3. When a definition concerns an adjective, the adjective and
associated noun are also in bold.
The committee has decided that the contents of this publication will remain unchanged until
2004. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
The following differences exist in the countries indicated below.
– 6.1: class 01 appliances are allowed (Japan).
– 6.1: class 0 and 01 appliances are allowed (South Africa, Poland).
A bilingual version of this publication may be issued at a later date.

– 6 – 60335-2-88  IEC:2002(E)
INTRODUCTION
It has been assumed in the drafting of this International Standard that the execution of its
provisions is entrusted to appropriately qualified and experienced persons.
This standard recognizes the internationally accepted level of protection against hazards such
as electrical, mechanical, thermal, fire and radiation of appliances when operated as in
normal use taking into account the manufacturer's instructions. It also covers abnormal
situations that can be expected in practice.
This standard takes into account the requirements of IEC 60364 as far as possible so that
there is compatibility with the wiring rules when the appliance is connected to the supply
mains. However, national wiring rules may differ.
If an appliance within the scope of this standard also incorporates functions that are covered
by another part 2 of IEC 60335, the relevant part 2 is applied to each function separately, as
far as is r
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