prEN IEC 60335-2-90:2026

SLOVENSKI STANDARD
01-september-2026
Gospodinjski in podobni električni aparati - Varnost - 2-90. del: Posebne zahteve
za mikrovalovne pečice za komercialno uporabo
Household and similar electrical appliances - Safety - Part 2-90: Particular requirements
for commercial microwave ovens
Sicherheit elektrischer Geräte für den Hausgebrauch und ähnliche Zwecke - Teil 2-90:
Besondere Anforderungen für gewerbliche Mikrowellenkochgeräte
Appareils électrodomestiques et analogues - Sécurité - Partie 2-90: Exigences
particulières pour les fours à micro-ondes à usage commercial
Ta slovenski standard je istoveten z: prEN IEC 60335-2-90:2026
ICS:
97.040.20 Štedilniki, delovni pulti, Cooking ranges, working
pečice in podobni aparati tables, ovens and similar
appliances
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD DRAFT
prEN IEC 60335-2-90
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2026
ICS 97.040.20 Will supersede EN IEC 60335-2-90:2021; EN IEC 60335-
2-90:2021/A1:2021
English Version
Household and similar electrical appliances - Safety - Part 2-90:
Particular requirements for commercial microwave ovens
(IEC 60335-2-90:2024)
Appareils électrodomestiques et analogues - Sécurité - Sicherheit elektrischer Geräte für den Hausgebrauch und
Partie 2-90: Exigences particulières pour les fours à micro- ähnliche Zwecke - Teil 2-90: Besondere Anforderungen für
ondes à usage commercial gewerbliche Mikrowellenkochgeräte
(IEC 60335-2-90:2024) (IEC 60335-2-90:2024)
This draft European Standard is submitted to CENELEC members for enquiry.
Deadline for CENELEC: 2026-10-01.
The text of this draft consists of the text of IEC 60335-2-90:2024.
If this draft becomes a European Standard, CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
This draft European Standard was established by CENELEC in three official versions (English, French, German).
A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to
the CEN-CENELEC Management Centre has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Project: 80431 Ref. No. prEN IEC 60335-2-90:2026 E

1 European foreword
2 This document (prEN IEC 60335-2-90:2026) consists of the text of IEC 60335-2-90:2024 prepared by
3 IEC/TC 61 "Safety of household and similar electrical appliances".
4 This document is currently submitted to the Enquiry.
5 The following dates are proposed:
• latest date by which the existence of this (doa) dav + 6 months
document has to be announced at national
level
• latest date by which this document has to be (dop) dav + 12 months
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) dav + 36 months
conflicting with this document have to be (to be confirmed or
withdrawn modified when voting)
6 This document will supersede EN IEC 60335-2-90:2021 and all of its amendments and corrigenda (if any).
7 This document is read in conjunction with prEN IEC 60335-2-90:2026/prAA:2026.
8 This document has been prepared under a standardization request addressed to CENELEC by the European
9 Commission. The Standing Committee of the EFTA State subsequently approves these requests for its
10 Member States.
11 For relationship with EU legislation, see informative Annexes ZZA, ZZB and ZZC, which are an integral part of
12 prEN IEC 60335-2-90:2026/prAA:2026.
IEC 60335-2-90 ®
Edition 5.0 2024-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household and similar electrical appliances – Safety –

Part 2-90: Particular requirements for commercial microwave ovens

Appareils électrodomestiques et analogues – Sécurité –

Partie 2-90: Exigences particulières pour les fours à micro-ondes à usage

commercial
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 97.040.20  ISBN 978-2-8322-9185-6

– 2 – IEC 60335-2-90:2024 © IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 9
3 Terms and definitions . 10
4 General requirement . 13
5 General conditions for the tests . 13
6 Classification . 14
7 Marking and instructions . 14
8 Protection against access to live parts . 16
9 Starting of motor-operated appliances . 17
10 Power input and current . 17
11 Heating . 17
12 Charging of metal-ion batteries . 20
13 Leakage current and electric strength at operating temperature . 20
14 Transient overvoltages . 20
15 Moisture resistance . 21
16 Leakage current and electric strength . 21
17 Overload protection of transformers and associated circuits . 22
18 Endurance . 22
19 Abnormal operation . 23
20 Stability and mechanical hazards . 25
21 Mechanical strength . 26
22 Construction . 28
23 Internal wiring . 33
24 Components . 33
25 Supply connection and external flexible cords . 33
26 Terminals for external conductors . 34
27 Provision for earthing . 34
28 Screws and connections . 34
29 Clearances, creepage distances and solid insulation . 34
30 Resistance to heat and fire . 34
31 Resistance to rusting . 35
32 Radiation, toxicity and similar hazards . 35
Annexes . 38
Annex A (informative) Routine tests . 39
Annex R (normative) Software evaluation . 41
Annex AA (normative) Combination microwave ovens . 42
Annex BB (normative) Requirements for commercial microwave ovens without a cavity
door and with conveyor-type means . 44
Annex CC (informative) Overview of the requirements for covers, means of access
and similar . 58

IEC 60335-2-90:2024 © IEC 2024 – 3 –
Annex DD (informative) Rationales for the microwave barrier and associated leakage
tests . 60
Annex EE (normative) Microwave ovens intended to be used on board ships . 66
Bibliography . 70

Figure 101 – Test rod for door interlock concealment . 36
Figure 102 – Probe for measuring surface temperatures . 36
Figure 103 – Front view of appliance with identification of excluded areas . 37
Figure BB.201 – Splash apparatus . 55
Figure BB.202 – Arrangement for measurement of microwave leakage from access
openings . 56
Figure BB.203 – Examples of definitions of Clause 3 . 57

Table 101 – Maximum temperature rises of external accessible surfaces under normal
operating conditions . 19
Table 102 – Maximum temperature rises of external accessible surfaces for appliances
intended to be used in areas open to the public under normal operating conditions . 20
Table 103 – Number of potatoes . 24
Table BB.201 – Specifications for microwave barriers . 51
Table BB.202 – Assembling torques for screwed connections providing earthing
continuity . 53
Table CC.1 – Overview of the requirements for covers, means of access and similar . 59
Table EE.201 – Assembling torques for screwed connections providing earthing
continuity . 68

– 4 – IEC 60335-2-90:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-90: Particular requirements for commercial microwave ovens

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 non-governmental 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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 60335-2-90 has been prepared by subcommittee 61B: Safety of microwave appliances for
household and commercial use, of IEC technical committee 61: Safety of household and similar
electrical appliances. It is an International Standard.
This fifth edition cancels and replaces the fourth edition published in 2015 including its
Amendment 1:2019. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the appliance used in area open to the public has been introduced in Clause 1, 3.8.107,
7.12, 8.1.1, 11.8, 20.2, 22.103.2, 22.105 and 22.117;
b) Subclauses 5.5, 7.12.1, 11.2, 11.7, 20.1 and 20.101 have been modified to add for stacking
installation;
IEC 60335-2-90:2024 © IEC 2024 – 5 –
c) Subclauses 7.1, 11.7 and 22.61 have been modified for the appliance outlets and socket-
outlets;
d) Subclause 7.12 has been improved in clarity;
e) maximum temperature rises of external accessible surfaces have been added in
Subclause 11.8;
f) test criterion has been modified in Subclause 15.101;
g) Subclause 16.101 has been modified to move the content of 16.101.1, 16.101.2 directly
under 16.101.
h) Subclauses 19.11.2, 19.13, Clause 21, Subclauses 22.105, 22.111 and Annex AA have
been improved in clarity;
i) Annex BB and Annex EE have been modified to add screw requirements.
The text of this International Standard is based on the following documents:
Draft Report on voting
61B/702/FDIS 61B/706/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts of the IEC 60335 series, under the general title: Household and similar
electrical appliances – Safety, can be found on the IEC website.
This part 2 is to be used in conjunction with the latest edition of IEC 60335-1 and its
amendments unless that edition precludes it; in that case, the latest edition that does not
preclude it is used. It was established on the basis of the sixth edition (2020) 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: Particular requirements for commercial microwave ovens.
When a particular subclause of Part 1 is not mentioned in 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 type in the text are defined in Clause 3. When a definition concerns an adjective, the adjective and
the associated noun are also in bold.

– 6 – IEC 60335-2-90:2024 © IEC 2024
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
NOTE 4 The attention of National Committees is drawn to the fact that equipment manufacturers and testing
organizations can need a transitional period following publication of a new, amended or revised IEC publication in
which to make products in accordance with the new requirements and to equip themselves for conducting new or
revised tests.
It is the recommendation of the committee that the content of this publication be adopted for implementation nationally
not earlier than 12 months or later than 36 months from the date of publication.
The following differences exist in the countries indicated below.
– 5.3:
Microwave leakage is not to exceed 10 W/m during the initial test (Japan,
USA and Canada).
– 6.1: Microwave ovens may be class 0I if the rated voltage does not exceed more
than 150 V (Japan).
– 7.12: Some warnings have to be marked on the appliance and be visible to the user
(Canada).
– Clause 18: The test is carried out on two appliances (USA).
– 19.11.2: The input voltage variation is not applied (USA).
– 19.13: Microwave leakage is only measured at the end of each test (USA).
– 21.102: The applied force is 222 N (USA).
– 21.105:
Microwave leakage is not to exceed 50 W/m (Japan and USA).
– 22.111: Microwave leakage is only measured at the end of the test (USA).
– 22.112:
Microwave leakage is not to exceed 50 W/m (Japan and USA).
– 22.116: All access to the cavity has to be prevented (USA).
– 27.2: A terminal for an external equipotential conductor is not required (Japan).

IEC 60335-2-90:2024 © IEC 2024 – 7 –
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.
Guidance documents concerning the application of the safety requirements for appliances can
be accessed via TC 61 and SC 61B supporting documents on the IEC website
https://www.iec.ch/tc61/supportingdocuments
https://www.iec.ch/sc61b/supportingdocuments
This information is given for the convenience of users of this International Standard and does
not constitute a replacement for the normative text in this standard.
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 and takes into account the way in which electromagnetic
phenomena can affect the safe operation of appliances.
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 can 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 reasonable. If applicable, the influence of one function on the other is taken into
account.
When a part 2 standard does not include additional requirements to cover hazards dealt with in
Part 1, Part 1 applies.
NOTE 1 This means that the technical committees responsible for the part 2 standards have determined that it is
not necessary to specify particular requirements for the appliance in question over and above the general
requirements.
This standard is a product family standard dealing with the safety of appliances and takes
precedence over horizontal and generic standards covering the same subject.
NOTE 2 Horizontal publications, basic safety publications and group safety publications covering a hazard are not
applicable since they have been taken into consideration when developing the general and particular requirements
for the IEC 60335 series of standards.
An appliance that complies with the text of this standard will not necessarily be considered to
comply with the safety principles of the standard if, when examined and tested, it is found to
have other features which impair the level of safety covered by these requirements.
An appliance employing materials or having forms of construction differing from those detailed
in the requirements of this standard can be examined and tested according to the intent of the
requirements and, if found to be substantially equivalent, may be considered to comply with the
standard.
NOTE 3 Standards dealing with non-safety aspects of household appliances are:
– IEC standards published by TC 59 concerning methods of measuring performance;
– CISPR 11, CISPR 14-1 and relevant IEC 61000-3 series standards concerning electromagnetic emissions;
– CISPR 14-2 concerning electromagnetic immunity;
– IEC standards published by TC 111 concerning environmental matters.

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HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-90: Particular requirements for commercial microwave ovens

1 Scope
This clause of Part 1 is replaced by the following.
This part of IEC 60335 deals with:
– the safety of microwave ovens with a cavity door intended for commercial use, their rated
voltage being not more than 250 V for single-phase appliances connected between one
phase and neutral and 480 V for other appliances.
These appliances are not intended for household and similar purposes. They are used for
commercial processing of food, also in areas open to the public, for example in kitchens
of restaurants, canteens, hospitals and in commercial enterprises such as bakeries and
butcheries;
– the safety of combination microwave ovens with a cavity door, the requirements of which
are contained in normative Annex AA;
– the safety of microwave ovens without a cavity door and with transportation means that
are intended for commercial use only, for the heating of food and beverages, the
requirements of which are contained in normative Annex BB.
Microwave ovens covered by normative Annex BB have transportation means for moving the
load through the microwave oven. Requirements for tunnel microwave ovens and several
types of microwave vending machines are covered.
This standard also deals with microwave ovens intended to be used on board ships, for which
normative Annex EE is applicable.
In normative Annex BB, a microwave oven without a cavity door and with transportation
means is described as a microwave oven. All clauses of this standard apply to these
appliances unless otherwise specified in normative Annex BB.
This part of IEC 60335 also takes into account ordinary persons having access to the
removing area of the vending machine.
The appliance can be built into a vending machine, in which case IEC 60335-2-75 can also be
applicable.
Appliances that use non-electrical energy are within the scope of this standard.
As far as is practicable, this standard deals with the common hazards presented by these types
of appliances.
This standard does not take into account the use of a microwave oven without a cavity door
and with transportation means by ordinary persons except in the vicinity of entrance and
exit ports.
The rationales for particular microwave exposure conditions and measures related to microwave
energy being confined by an open structure are given in normative Annex BB.

IEC 60335-2-90:2024 © IEC 2024 – 9 –
Attention is drawn to the fact that
– for appliances intended to be used in vehicles or on trains, on board ships or board aircraft,
additional requirements can be necessary;
– for appliances intended to be used in tropical countries, special requirements can be
necessary;
– in many countries, the national health authorities, the national authorities responsible for
the protection of labour and similar authorities specify additional requirements;
– in many countries, national authorities specify additional requirements to BB.22.101.1.
This standard does not apply to
– Microwave ovens including combination microwave ovens for household use covered by
IEC 60335-2-25 and used in the following environments by laymen:
• staff kitchen areas in shops, offices and other working environments;
• farm houses;
• by clients in hotels, motels and other residential type environments;
• bed and breakfast type environments.
– industrial microwave heating equipment (IEC 60519-6);
– appliances for medical purposes (IEC 60601);
– appliances intended to be used in locations where special conditions prevail, such as the
presence of a corrosive or explosive atmosphere (dust, vapour or gas).
2 Normative references
This clause of Part 1 is applicable except as follows.
Addition:
IEC 60068-2-6, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)
IEC 60068-2-27, Environmental testing – Part 2-27: Tests – Test Ea and guidance: Shock
IEC 60068-2-52, Environmental testing – Part 2-52: Tests – Test Kb: Salt mist, cyclic (sodium
chloride solution)
IEC 60335-2-36, Household and similar electrical appliances – Safety – Part 2-36: Particular
requirements for commercial electric cooking ranges, ovens, hobs and hob elements
IEC 60335-2-42, Household and similar electrical appliances – Safety – Part 2-42: Particular
requirements for commercial electric forced convection ovens, steam cookers and steam-
convection ovens
IEC 60335-2-49, Household and similar electrical appliances − Safety − Part 2-49: Particular
requirements for commercial electric appliances for keeping food and crockery warm
IEC 60335-2-75, Household and similar electrical appliances – Safety – Part 2-75: Particular
requirements for commercial dispensing appliances and vending machines
IEC 60436:2015, Electric dishwashers for household use – Methods for measuring the
performance
IEC 60436:2015/AMD1:2020
IEC 60584-1, Thermocouples – Part 1: EMF specifications and tolerances

– 10 – IEC 60335-2-90:2024 © IEC 2024
ISO 898-1, Mechanical properties of fasteners made of carbon steel and alloy steel – Part 1:
Bolts, screws and studs with specified property classes – Coarse thread and fine pitch thread
ISO 3506-1, Fasteners – Mechanical properties of corrosion-resistant stainless steel fasteners
– Part 1: Bolts, screws and studs with specified grades and property classes
ISO 3506-2, Fasteners – Mechanical properties of corrosion-resistant stainless steel fasteners
– Part 2: Nuts with specified grades and property classes
ISO 3506-3, Mechanical properties of corrosion-resistant stainless steel fasteners – Part 3: Set
screws and similar fasteners not under tensile stress
ISO 3506-4, Mechanical properties of corrosion-resistant stainless steel fasteners – Part 4:
Tapping screws
3 Terms and definitions
This clause of Part 1 is applicable except as follows.
3.1 Definitions relating to physical characteristics
3.1.7
Note 101 to entry: The rated frequency is the input frequency.
3.1.9
normal operation
Modification:
Replace the first paragraph by the following:
operation of the appliance under the following conditions:
The appliance is operated with 1 000 g ± 50 g of potable water at an initial temperature of 20 °C
± 2 °C in a cylindrical borosilicate glass vessel having a maximum thickness of 3 mm and an
outside diameter of approximately 190 mm. The vessel is placed on the centre of the shelf. If
the rated microwave power output exceeds 2 200 W, two such vessels are used and placed
contiguously in the cavity.
3.1.101
rated microwave power output
microwave power output assigned to the appliance by the manufacturer
3.5 Definitions relating to types of appliances
3.5.101
microwave oven
appliance using electromagnetic energy in one or several of the ISM frequency bands between
300 MHz and 30 GHz, for heating food and beverages in a cavity
Note 1 to entry: ISM frequency bands are the electromagnetic frequencies established by the ITU and reproduced
in CISPR 11.
3.5.102
combination microwave oven
microwave oven in which heat is also provided in the cavity by simultaneous or consecutive
operation of resistive heating elements
Note 1 to entry: The resistive heating elements are used to provide radiant heat, convection heat or steam.

IEC 60335-2-90:2024 © IEC 2024 – 11 –
3.6 Definitions relating to parts of an appliance
3.6.101
cavity
space enclosed by the inner walls and the door in which the load is placed
3.6.102
shelf
horizontal support in the cavity on which the load is placed
3.6.103
door interlock
device or system that prevents the operation of the microwave generator(s), unless the oven
door is closed
3.6.104
monitored door interlock
door interlock system that incorporates a supervision device
3.6.105
temperature-sensing probe
device that is inserted into the food to measure its temperature and is a part of an oven control
3.6.106
transportation means
means to transport the load through the microwave oven
Note 1 to entry: An example of a transportation means is a belt, an arm or an inclined plane.
3.6.107
microwave enclosure
structure that is intended to confine microwave energy to a defined region
Note 1 to entry: Barriers mounted outside the microwave enclosure are not considered a part of the microwave
enclosure.
Note 2 to entry: A microwave enclosure can consist of a cavity, quarter wave chokes (acting by impedance trans-
formation), mode chokes (acting by field pattern mismatching) and microwave energy absorbers.
3.6.108
microwave barrier
physical barrier, which is microwave transparent, limiting access to the microwave enclosure,
mounted outside the microwave enclosure and can only be removed with the aid of tools
Note 1 to entry: A microwave barrier can be mounted between the microwave enclosure and the external cover
of the appliance.
Note 2 to entry: Devices such as an array of metal chains or hinged metal plates at entrance and exit ports
intended to reduce microwave leakage are not considered microwave barriers.
Note 3 to entry: Construction requirements are given in BB.22.101.
Note 4 to entry: Informative Annex DD mentions about rationale for the microwave barrier and associated leakage
test.
3.6.109
entrance and exit ports
openings in the microwave enclosure through which loads move
3.6.110
loading area
area on which the load is placed

– 12 – IEC 60335-2-90:2024 © IEC 2024
3.6.111
means of monitored microwave interlock
means of microwave interlock that incorporates a supervision device
3.6.112
protective blocking structure
movable mechanical structure located in the removing area limiting access to the microwave
enclosure
3.6.113
removing area
area from which the load is removed
3.6.114
viewing opening
opening in the cavity through which the warm up process can be visually monitored
3.6.115
fixed means of connection
all parts of the microwave enclosure that are permanently open with the exception of entrance
and exit ports and viewing openings
Note 1 to entry: Fixed means of connection can be used for venting and water flushing.
3.6.116
Void
3.6.117
means of microwave interlock
mechanical or electrical safety devices or systems that operate when certain conditions are not
fulfilled (e.g. an interlock system that prevents the operation of the microwave generator when
a means of access is open)
3.6.118
maintenance cover
structural feature of any part of the equipment that can be opened or removed by the use of a
tool to provide access for routine maintenance, service, replacement of expendable parts, etc.
in microwave containing areas
3.6.119
cleaning cover
part of the microwave enclosure that can be opened or removed, only with the aid of a tool,
for frequent cleaning purposes, during operation
3.6.120
reference surface
surface in the vicinity of entrance and exits ports defined depending on the reading of
microwave leakage of 32.1 of normative Annex BB
Note 1 to entry: If the leakage reading is less or equal to 50 W/m , the reference surface is the surface of the
geometric opening of the microwave enclosure without microwave barrier.
Note 2 to entry: If the leakage reading exceeds 50 W/m , the reference surface is an artificial surface located
50 mm away from the locations where the sensor of the instrument measures leakage readings of 50 W/m straight
inwards towards the appliance.
Note 3 to entry: For further explanation, refer to 32.1 of normative Annex BB.

IEC 60335-2-90:2024 © IEC 2024 – 13 –
3.8 Definitions relating to miscellaneous matters
3.8.101
instructed person
person who is sufficiently instructed and monitored to know how to avoid any danger caused by
the operation of microwave ovens
3.8.102
skilled person
person with suitable professional education, knowledge and experience to discern and to avoid
any danger caused by the operation of microwave ovens
3.8.103
ordinary person
person who is neither a skilled person nor an instructed person
3.8.104
load
food and beverages that can be heated up in a microwave oven
3.8.105
area open to the public
area in which the general public, including children, can have access
Note 1 to entry: Examples include customer areas in:
– grocery stores;
– canteens;
– train stations;
– self-service restaurants.
3.8.106
open deck
area that is exposed to marine environment
3.8.107
dayroom
area that can be exposed to marine environment from time to time
4 General requirement
This clause of Part 1 is applicable.
5 General conditions for the tests
This clause of Part 1 is applicable except as follows.
5.2 Addition:
An additional sample can be required for the test of 19.104.
Six samples of the interlocks are required for the test of 24.1.4.

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5.3 Modification:
Instead of carrying out the tests in the order of clauses, the following sequence of clauses and
subclauses applies: 32.1, 22.113, 22.108, 22.116, Clause 7 to Clause 17, Clause 20,
Clause 21 (except 21.101 to 21.105), Clause 18, Clause 19 (except 19.104), Clause 22 (except
22.108, 22.113 and 22.116), Clause 23 to Clause 31 and 32.2, 21.101 to 21.105 and 19.104.
5.5 Addition:
The tests are carried out with the appliances in any stacked combination or any movable part
of it placed in the most unfavourable condition that can occur in normal use.
5.101 Microwave ovens are tested as motor-operated appliances.
5.102 Class III temperature-sensing probes are only subjected to the tests of 22.112.
6 Classification
This clause of Part 1 is applicable except as follows.
6.1 Modification:
Microwave ovens shall be class I.
7 Marking and instructions
This clause of Part 1 is applicable except as follows.
7.1 Addition:
Appliances shall be marked with the nominal frequency in megahertz of the ISM band in which
they operate.
If the removal of any cover results in microwave leakage exceeding the value specified in 32.1,
the cover shall be marked with the substance of the following:
WARNING: Microwave energy – Do not remove this cover
If appliances have external enclosures, other than working surfaces, that cannot meet the limit
in Table 3 specified for external enclosures of motor-operated appliances, they shall be
marked with symbol IEC 60417-5041 (2002-10) or with the substance of the following:
CAUTION: Hot surface.
If appliances have external accessible surfaces, for which temperature rise limits are specified
in Table 101 and Table 102 and for which the provisions of footnote b to Table 101 and
Table 102 apply, then the appliance shall be marked with symbol IEC 60417-5041 (2002-10) or
with the substance of the following:
CAUTION: Hot surface
IEC 60335-2-90:2024 © IEC 2024 – 15 –
7.6 Addition:
[symbol IEC 60417-5021
equipotentiality
(2002-10)]
[symbol IEC 60417-5041
caution, hot surface
(2002-10)]
7.12 Addition:
The instructions shall include the substance of the following:
– WARNING: If the door or door seals are damaged, the oven must not be operated until it
has been repaired by a competent person.
– WARNING: It is hazardous for anyone other than a competent person to carry out any
service or repair operation that involves the removal of any cover which gives protection
against exposure to microwave energy.
NOTE 101 This warning is applicable if microwave leakage exceeds the limit specified in 32.1 during the
removal of any cover.
– WARNING: Liquids or other foods must not be heated in sealed containers since they are
liable to explode.
– WARNING: Microwave heating of beverages can result in delayed eruptive boiling, therefore
care must be taken when handling the container.
– WARNING: The contents of feeding bottles and baby food jars must be stirred or shaken
and the temperature checked before consumption, in order to avoid burns.
– The minimum height of free space necessary above the top surface of the oven.
– Only use utensils that are suitable for use in microwave ovens.
– When heating food in plastic or paper containers, keep an eye on the oven due to the
possibility of ignition.
– If smoke is observed, switch off or unplug the appliance and keep the door closed in order
to stifle any flames.
– Eggs in their shell and whole hard-boiled eggs should not be heated in microwave ovens
since they may explode even after microwave heating has ended.
– Details for cleaning door seals, cavities and adjacent parts.
– The oven should be cleaned regularly and any food deposits removed.
– Failure to maintain the oven in a clean condition could lead to deterioration of the surface
that could adversely affect the life of the appliance and possibly result in a hazardous
situation.
– Only use the temperature probe recommended for this o
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