IEC 60749-20-1:2019

IEC 60749-20-1 ®
Edition 2.0 2019-06
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices – Mechanical and climatic test methods –
Part 20-1: Handling, packing, labelling and shipping of surface-mount devices
sensitive to the combined effect of moisture and soldering heat

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IEC 60749-20-1 ®
Edition 2.0 2019-06
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices – Mechanical and climatic test methods –

Part 20-1: Handling, packing, labelling and shipping of surface-mount devices

sensitive to the combined effect of moisture and soldering heat

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.01 ISBN 978-2-8322-7124-7

– 2 – IEC 60749-20-1:2019 RLV © IEC:2019
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 General applicability and reliability considerations . 10
4.1 Assembly processes . 10
4.1.1 Mass reflow . 10
4.1.2 Localized heating. 10
4.1.3 Socketed components . 10
4.1.4 Point-to-point soldering . 11
4.1.5 Aqueous cleaning . 11
4.2 Reliability . 11
5 Dry packing . 11
5.1 Requirements . 11
5.2 Drying of SMDs and carrier materials before being sealed in MBBs . 11
5.2.1 Drying requirements – level A2 . 11
5.2.2 Drying requirements – levels B2a to B5a . 12
5.2.3 Drying requirements – carrier materials . 12
5.2.4 Drying requirements – other . 12
5.2.5 Excess time between bake and bag . 12
5.3 Dry pack . 12
5.3.1 Description . 12
5.3.2 Materials . 13
5.3.3 Labels . 16
5.3.4 Moisture barrier bag sealing . 17
5.3.5 Dry pack precautions . 17
5.3.6 Shelf life . 17
6 Drying. 17
6.1 Drying options . 17
6.2 Post exposure to factory ambient . 22
6.2.1 Floor life clock . 22
6.2.2 Any duration exposure . 22
6.2.3 Short duration exposure . 22
6.3 General considerations for baking . 22
6.3.1 High-temperature carriers . 22
6.3.2 Low-temperature carriers . 22
6.3.3 Paper and plastic container items . 23
6.3.4 Bakeout times . 23
6.3.5 ESD protection . 23
6.3.6 Reuse of carriers . 23
6.3.7 Solderability limitations . 23
7 Use . 23
7.1 Floor life clock start . 23
7.2 Incoming bag inspection . 23

7.2.1 Upon receipt . 23
7.2.2 Component inspection . 24
7.3 Floor life . 24
7.4 Safe storage . 24
7.4.1 Safe storage categories . 24
7.4.2 Dry pack . 24
7.4.3 Shelf life . 24
7.4.4 Dry atmosphere cabinet . 25
7.5 Reflow . 25
7.5.1 Reflow categories . 25
7.5.2 Opened MBB . 25
7.5.3 Reflow temperature extremes . 25
7.5.4 Additional thermal profile parameters. 25
7.5.5 Multiple reflow passes . 26
7.5.6 Maximum reflow passes . 26
7.6 Drying indicators . 26
7.6.1 Drying requirements . 26
7.6.2 Excess humidity in the dry pack . 26
7.6.3 Floor life or ambient temperature/humidity exceeded . 27
7.6.4 Level B6 SMDs . 27
Annex A (normative) Symbol and labels for moisture-sensitive devices . 28
A.1 Object . 28
A.2 Symbol and labels. 28
A.2.1 "Moisture-sensitive" symbol . 28
A.2.2 Moisture-sensitive identification (MSID) label . 28
A.2.3 Moisture-sensitive caution labels . 28
Annex B (informative) Board rework . 32
B.1 Component removal, rework and remount . 32
B.1.1 Removal precautions . 32
B.1.2 Removal for failure analysis . 32
B.1.3 Removal and remount . 32
B.2 Baking of populated boards. 32
Annex C (normative) Test method for humidity indicator cards used with electronic
component packaging . 33
C.1 HIC testing method . 33
C.2 Testing apparatus . 33
C.3 Testing procedure . 33
C.4 Data analysis . 34
Annex D (informative) Derivation of bake tables . 35
Annex E (informative) Derating due to factory environmental conditions . 37
Bibliography . 41

Figure 1 – Typical dry pack configuration for moisture-sensitive SMDs
in shipping tubes . 13
Figure 2 – Example humidity indicator cards . 16
Figure A.1 – Moisture-sensitive symbol (example) . 28
Figure A.2 – MSID label (example) . 28
Figure A.3 – Information label for level A1 or B1 (example) . 29

– 4 – IEC 60749-20-1:2019 RLV © IEC:2019
Figure A.4 – Moisture-sensitive caution label for level A2 (example) . 29
Figure A.5 – Moisture-sensitive caution label for levels B2-B5a (example) . 30
Figure A.6 – Moisture-sensitive caution label for level B6 (example) . 31
Figure D.1 –Typical moisture concentration over time . 35

Table 1 – Dry packing requirements . 11
Table 2 –Typical HIC spot compliance . 15
Table 3 – Reference conditions for drying mounted or unmounted SMDs (user bake:
floor life begins counting at time = 0 after bake) – Level 2. 18
Table 4 – Reference conditions for drying mounted or unmounted SMDs (user bake:
floor life begins counting at time = 0 after bake) – Levels B2, B2a to B5a . 20
Table 5 – Default baking times used prior to dry-pack that were exposed to conditions
≤ 60 % RH (supplier bake: MET = 24 h) . 21
Table 6 – Resetting or pausing the ‘floor life’ clock at user site . 21
Table 7 – Moisture classification level and floor life . 24
Table C.1 – HIC spot compliance . 33
Table E.1 – Recommended equivalent total floor life (days) for level A2 at 20 °C, 25 °C,
30 °C and 35 °C for ICs with novolac, biphenyl and multifunctional epoxies (reflow at
same temperature at which component was classified) . 38
Table E.2 – Recommended equivalent total floor life (days) for levels B2a to B5a at
20 °C, 25 °C, 30 °C and 35 °C for ICs with novolac, biphenyl and multifunctional
epoxies (reflow at same temperature at which component was classified) . 39

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –

Part 20-1: Handling, packing, labelling and shipping of surface-mount
devices sensitive to the combined effect of moisture and soldering heat

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition. A vertical bar appears in the margin wherever a change
has been made. Additions are in green text, deletions are in strikethrough red text.

– 6 – IEC 60749-20-1:2019 RLV © IEC:2019
This second edition cancels and replaces the first edition published in 2009. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) updates to subclauses to better align the test method with IPC/JEDEC J-STD-033C,
including new sections on aqueous cleaning and dry pack precautions;
b) addition of two annexes on colorimetric testing of HIC (humidity indicator card) and
derivation of bake tables.
The text of this standard is based on the following documents:
FDIS Report on voting
47/2565/FDIS 47/2579/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 publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60749 series, published under the general title Semiconductor
devices – Mechanical and climatic test methods, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

INTRODUCTION
The advent of surface-mount devices (SMDs) introduced a new class of quality and reliability
concerns regarding package damage "cracks and delamination" from the solder reflow
process. This document describes the standardized levels of floor life exposure for
moisture/reflow-sensitive SMDs along with the handling, packing and shipping requirements
necessary to avoid moisture/reflow-related failures. IEC 60749-20 defines the classification
procedure and Annex A of this document defines the labelling requirements.
Moisture from atmospheric humidity enters permeable packaging materials by diffusion.
Assembly processes used to solder SMDs to printed circuit boards (PCBs) expose the entire
package body to temperatures higher than 200 °C. During solder reflow, the combination of
rapid moisture expansion, materials mismatch, and material interface degradation can result
in package cracking and/or delamination of critical interfaces within the package.
The solder reflow processes of concern are convection, convection/IR, infrared (IR), vapour
phase (VPR) and hot air rework tools. The use of assembly processes that immerse the
component body in molten solder are not recommended for most SMDs.
This first edition of IEC 60749-20-1 is based principally on IPC/JEDEC J-STD-033 and the
permission to use this standard is gratefully acknowledged. It is also based on contributing
documents from various national committees.
Typical solder reflow processes of concern for all devices are infrared (IR), convection/IR,
convection, vapour phase reflow (VPR), hot air rework tools, and wave solder, including full
immersion.
Non-semiconductor devices can exhibit additional process sensitivities beyond moisture
sensitivity such as thermal sensitivity, flux sensitivity, or cleaning process sensitivity.
___________
Refer to Bibliography.
– 8 – IEC 60749-20-1:2019 RLV © IEC:2019
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –

Part 20-1: Handling, packing, labelling and shipping of surface-mount
devices sensitive to the combined effect of moisture and soldering heat

1 Scope
This part of IEC 60749 applies to all non-hermetic SMD packages which are subjected to
reflow solder processes and devices subjected to bulk solder reflow processes during PCB
assembly, including plastic encapsulated packages, process sensitive devices, and other
moisture-sensitive devices made with moisture-permeable materials (epoxies, silicones, etc.)
that are exposed to the ambient air.
The purpose of this document is to provide SMD manufacturers and users with standardized
methods for handling, packing, shipping, and use of moisture/reflow sensitive SMDs that have
been classified to the levels defined in IEC 60749-20. These methods are provided to avoid
damage from moisture absorption and exposure to solder reflow temperatures that can result
in yield and reliability degradation. By using these procedures, safe and damage-free reflow
can be achieved, with the dry packing process, providing a minimum shelf life capability in
sealed dry-bags from the seal date.
Two test conditions, method A and method B, are specified in the soldering heat test of
IEC 60749-20. For method A, moisture soak conditions are specified on the assumption that
moisture content inside the moisture barrier bag is less than 30 % RH. For method B,
moisture soaking conditions are specified on the assumption that manufacturer’s exposure
time (MET) does not exceed 24 h and the moisture content inside the moisture barrier bag is
less than 10 % RH. In an actual handling environment, SMDs tested by method A are
permitted to absorb moisture up to 30 % RH, and SMDs tested by method B are permitted to
absorb moisture up to 10 % RH. This document specifies the handling conditions for SMDs
subjected to the above test conditions.
NOTE Hermetic SMD packages are not moisture sensitive and do not require moisture precautionary handling.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60749-20, Semiconductor devices – Mechanical and climatic test methods – Part 20:
Resistance of plastic-encapsulated SMDs to the combined effect of moisture and soldering
heat
IEC 60749-30, Semiconductor devices – Mechanical and climatic test methods – Part 30:
Preconditioning of non-hermetic surface mount devices prior to reliability testing
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
active desiccant
desiccant that is either fresh (new) or has been baked according to the manufacturer’s
recommendations to renew it to original specifications
3.2
bar code label
label that gives information in a code consisting of parallel bars and spaces, each of various
specific widths
Note 1 to entry: For the purposes of this document, the bar code label is on the lowest level shipping container
and includes information that describes the product, e.g. part number, quantity, lot information, supplier
identification, and moisture-sensitivity level etc.
3.3
mass reflow
reflow of a number of components with simultaneous attachment by an infrared (IR),
convection/IR, convection, or vapour phase reflow (VPR) process
3.4
carrier
container that directly holds components such as a tray, tube, or tape and reel
3.5
desiccant
absorbent material used to maintain a low relative humidity
3.6
floor life
allowable time period for a moisture-sensitive device, after removal from a moisture barrier
bag, dry storage or dry bake and before the solder reflow process
3.7
humidity indicator card
HIC
card on which a moisture-sensitive chemical is applied in such a way that it will make a
significant, perceptible change in colour (hue), typically from blue (dry) to pink (wet) when the
indicated relative humidity is exceeded
card printed with a moisture-sensitive chemical (cobalt bromide) that changes from blue to
pink in the presence of water vapour
Note 1 to entry: The HIC is packed inside the moisture-barrier bag, along with a desiccant, to aid in determining
the level of moisture to which the moisture-sensitive devices have been subjected.
Note 2 to entry: This note applies to the French language only.
3.8
manufacturer’s exposure time
MET
maximum time after bake that the component manufacturer requires to process components
prior to bag seal, and that also includes the maximum time allowed at the distributor for
having the bag open to split out smaller shipments
Note 1 to entry: This note applies to the French language only.

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3.9
moisture barrier bag
MBB
bag designed to restrict the transmission of water vapour and used to pack moisture-sensitive
devices
storage bag manufactured with a flexible laminated vapour barrier film that restricts the
transmission of water vapour
Note 1 to entry: This note applies to the French language only.
3.10
rework
removal of a component for scrap, reuse, or failure analysis; replacement of an attached
component; or heating and repositioning of a previously attached component
3.11
shelf-life
maximum storage period for a dry-packed moisture-sensitive device in an unopened moisture
barrier bag (MBB) to avoid exceeding the specified interior bag ambient humidity
3.12
surface-mount device
SMD
plastic-encapsulated surface-mount devices made with moisture-permeable materials
Note 1 to entry: For the purposes of this document, the term "SMD" is limited as indicated in the above definition.
3.13
solder reflow
solder attachment process in which previously applied solder or solder paste is melted to
attach a component to the printed circuit board
3.14
water vapour transmission rate
WVTR
measure of the permeability of plastic film or metallized plastic film material to moisture
4 General applicability and reliability considerations
4.1 Assembly processes
4.1.1 Mass reflow
This document applies to mass solder reflow assembly by convection, convection/IR, infrared
(IR), and vapour phase (VPR), processes. It does not apply to mass solder reflow processes
that immerse the component bodies in molten solder (e.g. wave soldering bottom mounted
components). Such processes are not allowed for many SMDs and are not covered by the
component qualifications standards used as a basis for this document.
4.1.2 Localized heating
This document also applies to moisture-sensitive SMDs that are removed or attached singly
by local ambient heating, i.e. "hot air rework". See Annex B.
4.1.3 Socketed components
This document does not apply to SMDs that are socketed and not exposed to solder reflow
temperatures. Such SMDs are not at risk and do not require moisture precautionary handling.

4.1.4 Point-to-point soldering
This document does not apply to SMDs in which only the leads are heated to reflow the solder,
e.g. hand-soldering, hot bar attach of gull-wing leads, and through hole by wave soldering.
The heat absorbed by the SMD body from such operations is typically much lower than that
for mass surface mount reflow or hot air rework, and moisture precautionary measures are
typically not needed.
4.1.5 Aqueous cleaning
For non-cavity SMDs, typical short-term aqueous cleaning processes will not impact the floor
life (internal moisture content). Special consideration should be given to non-hermetic cavity
packages.
4.2 Reliability
The methods set forth in this specification ensure that an adequate SMD reliability can be
achieved during and after the PCB assembly operation, when the SMDs are evaluated and
verified by IEC 60749-20 and/or by IEC 60749-30, together with environmental reliability
testing.
This specification does not address or ensure solder joint reliability of attached components.
5 Dry packing
5.1 Requirements
Dry packing requirements for the various moisture sensitivity levels are shown in Table 1. The
levels are determined in accordance with IEC 60749-20 and/or IEC 60749-30, together with
reliability testing. As a minimum, all materials used in dry packing should conform to relevant
national packaging material standards for ESD-sensitive items.
Table 1 – Dry packing requirements
a
Level Dry before MBB Desiccant MSID label Caution label
bag
A1 or B1 Optional Optional Optional Not required Not required if classified at
220 °C to 225 °C
b
Required if classified at other
than 220 °C to 225 °C
A2 or B2 Optional Required Required Required Required
B2a-B5a Required Required Required Required Required
B6 Optional Optional Optional Required Required
a
MSID = moisture-sensitive identification label.
b
A "Caution" label is not required if level and reflow temperature are given, in human readable form, on the
barcode label attached to the lowest level shipping container.

5.2 Drying of SMDs and carrier materials before being sealed in MBBs
5.2.1 Drying requirements – level A2
Packing of the SMDs classified as Level A2 into MBBs shall be carried out within one week
under the environmental condition below 30 °C/60 % RH after moulding, burn-in, or bake.
MET is not specified for Level A2 SMDs.

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MBBs may be opened for a short period of time (less than 1 h) and re-closed provided that
the HIC indicates a humidity of less than 30 % RH and provided that the desiccant is replaced
with fresh desiccant. When the MBB is next opened, as long as the HIC indicates below
30 % RH, the duration time of the previous MBB’s opening may be disregarded. Thus, if the
HIC indicates below 30 % RH when MBB is opened, the floor life is not dependent on the
duration time of the MBB's opening, and is 168 h at 30 °C/70 % RH.
5.2.2 Drying requirements – levels B2a to B5a
SMDs classified from Levels B2a through to B5a shall be dried (see Clause 6) prior to being
sealed in MBBs. The period between drying and sealing shall not exceed the MET less the
time allowed for distributors to open the bags and repack parts. If the supplier’s actual MET is
more than the default 24 h, then the actual time shall be used. If the distributor practice is to
repack the MBBs with active desiccant, then this time does not need to be subtracted from the
MET.
5.2.3 Drying requirements – carrier materials
The materials from which carriers (such as trays, tubes, reels, etc.) are made can affect the
moisture level when placed in the MBB. Therefore, the effect of these materials shall be
compensated for by baking or, if required, adding additional desiccant in the MBB to ensure
the shelf life of the SMDs (see 6.3).
5.2.4 Drying requirements – other
Suppliers may use the drying effect of normal in-line processes such as post-mould cure,
marking cure, and burn-in to reduce the bake time. An equivalency evaluation is
recommended to ensure that high-temperature processing maintains moisture weight gain to
an acceptable level. The total weight gain for the SMD at the time it is sealed in the MBB shall
not exceed the moisture gain of that SMD starting dry and then being exposed to
30 °C/60 % RH for MET h (less the time for distributors).
5.2.5 Excess time between bake and bag
If the allowable time between bake and bag is exceeded, the SMDs shall be redried in
accordance with Clause 6.
5.3 Dry pack
5.3.1 Description
A dry pack consists of desiccant material and a humidity indicator card (HIC) sealed with the
SMDs and their carriers inside a moisture barrier bag (MBB). A representative dry pack
configuration is shown in Figure 1.

Figure 1 – Typical dry pack configuration for moisture-sensitive
SMDs in shipping tubes
5.3.2 Materials
5.3.2.1 Moisture barrier bag (MBB)
The moisture barrier bag shall meet relevant national standard requirements for flexibility,
ESD protection, mechanical strength, and puncture resistance. The bags shall be heat-
sealable. The water vapour transmission rate (WVTR) shall be ≤ 0,03 g/m in 24 h at 40 °C
after flex testing in accordance with relevant national standards governing flex durability of
flexible barrier materials. The WVTR is measured using relevant national standards governing
water vapour transmission rate through plastic film and sheeting using a modulated infrared
sensor.
5.3.2.2 Desiccant
The desiccant material shall comply with relevant national standards governing activated
desiccants used for the static dehumidification of packaging bags. Desiccant shall be dustless,
non-corrosive, and absorbent to amounts specified in the standard. The desiccant shall be
packaged in moisture-permeable bags. The amount of desiccant used, per moisture barrier
bag, shall be based on the bag surface area and WVTR in order to maintain an interior
relative humidity in the MBB of less than 30 % at 25 °C for SMD classification A2 and less
than 10 % at 25 °C for SMDs classified from Levels B2a to B5a.
For comparison between various desiccant types, certain specifications adopted the "UNIT"
as the basic unit of measure of quantity for desiccant material. A UNIT of desiccant is defined
as the amount that will absorb a minimum of 2,85 g of water vapour at 20 % RH and 25 °C. To
meet the dry pack requirements of this document, the amount of water vapour that a UNIT of
desiccant can absorb at 10 % RH and 25 °C must shall be known.
When the desiccant capacity at 10 % RH and 25 °C is known, the following equation should
be used.
U = (0,003 × M × WVTR × A)/D (1)
where
U = amount of desiccant in UNITS;
M = shelf life desired in months;
WVTR = water vapour transmission rate in g/m in 24 h;

– 14 – IEC 60749-20-1:2019 RLV © IEC:2019
A = total surface area of the MBB in m ;
D = amount of water in grams, that a UNIT of desiccant will absorb at 10 % RH and 25 °C.
When the desiccant capacity at 10 % RH and 25 °C is not known, the quantity needed can be
estimated using the following simplified equation.
U = 8 × A (2)
where
U = amount of desiccant in UNITS;
A = total surface area of the MBB in m .
NOTE If trays, tubes, reels, foam end caps, etc., are placed in the bag without baking, additional desiccant will be
required to absorb the moisture contained in these materials.
If it is desired to minimize the amount of desiccant used for dry-packing level 2 components, a
value of D based on the amount of water in grams that a UNIT of desiccant will absorb at
60 % RH and 25 °C should be used in the formula. This value can be obtained from the
desiccant manufacturer. When this option is used, it can be verified that, when the component
was classified in accordance with IEC 60749-20, it has achieved full saturation during
moisture soak.
No moisture-absorbing material (e.g. trays, tubes, reels, foam end caps) should be placed in
the dry bag without baking. Any such material that is included increases the amount of
desiccant needed to meet the calculated shelf life (see 7.4.2) by an amount based on the
moisture content of the material. This can be determined by weighing a representative
quantity of material known to be at equilibrium with the manufacturing environment, baking to
a new constant weight, and subtracting the final from the initial weight. Additional UNIT(s) of
desiccant, based on 10 % RH at 25 °C, should be added to absorb the amount of water, in
grams, egressed from the packing materials (dunnage) after baking.
5.3.2.3 Desiccant handling and storage
Desiccant capacity decreases rapidly when exposed to 30 °C/60 % RH. Therefore, the
desiccant should remain in the manufacturer’s container or stored in a dry cabinet at < 5 %
RH until use. When dry packing, the desiccant shall be removed from the storage container
just prior to placing it into the MBB and sealing the MBB.
5.3.2.4 Humidity indicator card (HIC)
The HIC shall comply with relevant national standards governing chemically impregnated
humidity indicator cards. For level A2, the HIC shall have a sensitivity value of 30 % RH,
which may be indicated by colour dots with sensitivity values of 20 % RH, 30 % RH, 40 % RH.
For SMDs classified from Levels B2a through to B5a, as a minimum, the HIC shall have 3
colour dots with sensitivity values of 5 % RH, 10 % RH, 60 % RH. The spots shall indicate the
humidity with a significant and perceptible change in colour (hue) as indicated in Table 2. Hue
shall be tested using the test method in Annex C. The colours shall be described in writing on
the card. HIC reuse is not allowed if the 60 % spot has changed colour. Reuse is not allowed,
owing to loss of accuracy of the 5 % and 10 % spot chemistry, if the 60 % spot has changed
colour. It is not required to reuse the same HIC from the MBB if the MBB is to be resealed; a
fresh HIC may be used.
Examples of HIC are shown in Figures 2a) and 2b).
5.3.2.5 HIC paper
White blotting paper made from fibrous, cellulosic material, with a minimum basis weight of,
255 g/m2 shall be used for HICs.

5.3.2.6 Visual defects
HICs shall be free from defects including missing spots, tears, improperly located spots, and
indicating colour overrunning the black circles.
5.3.2.7 Preservation
HICs shall be stored in accordance with the manufacturer’s recommendation prior to insertion
in the MBB. At a minimum, the 10 % spot shall indicate dry when the cards are removed from
the original container.
Table 2 –Typical HIC spot compliance
Indication at Indication at Indication at Indication at Indication at Indication at
2 % RH 5 % RH 10 % RH 55 % RH 60 % RH 65 % RH
environment environment environment environment environment environment
5 % spot Blue Lavender Pink Pink Pink Pink
(dry) (spot value) (wet) (wet) (wet) (wet)
change ≤7 %
hue
10 % spot Blue Blue Lavender Pink Pink Pink
(dry) (dry) (spot value) (wet) (wet) (wet)
change
≤10 % hue
60 % spot Blue Blue Blue Blue Lavender Pink
(dry) (dry) (dry) (dry) (spot value) (wet)
change
≤10 % hue
NOTE Other colour schemes can be used.

– 16 – IEC 60749-20-1:2019 RLV © IEC:2019

Below 30 % RH can be confirmed by comparison of a colour (lavender).
a) Example of humidity indicator card for level A2

b) Example of humidity indicator card for levels B2a to B5a
Figure 2 – Example humidity indicator cards
5.3.3 Labels
5.3.3.1 Labels – Moisture sensitive identification
Labels relevant to the dry pack process are the moisture-sensitive identification (MSID) label
and the caution label as specified in Annex A (see Figures A.2 to A.5). The MSID label shall
be affixed to the lowest-level shipping container that contains the MBB. The caution label
shall be affixed to the outside surface of the MBB. The caution label includes fields for the
moisture classification level in accordance with IEC 60749-20; the peak package body
temperature allowed during reflow soldering (the classification temperature); the floor life; and
the bag seal date. If the calculated shelf life is greater than 12 months, item # 1 of the caution
label shall be changed accordingly.
5.3.3.2 Labels – Level B6 requirements
Level B6 parts not shipped in MBBs s
...