ISO/TS 17665-3:2013

TECHNICAL ISO/TS
SPECIFICATION 17665-3
First edition
2013-04-15
Sterilization of health care
products — Moist heat —
Part 3:
Guidance on the designation of a
medical device to a product family
and processing category for steam
sterilization
Stérilisation des produits de santé — Chaleur humide —
Partie 3: Directives concernant la désignation d’un dispositif médical
pour une famille de produits et catégorie de traitement pour la
stérilisation à la vapeur
Reference number
©
ISO 2013
© ISO 2013
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ii © ISO 2013 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Classification . 2
4.1 General attributes . 2
4.2 Detailed attributes . 2
5 Product family (pf) . 5
5.1 Example 1 — pf 1 . 6
5.2 Example 2 — pf 24. 6
5.3 Example 3 — pf 27. 7
6 Processing category . 8
7 Sterilization process parameters . 8
8 Additional considerations . 8
8.1 Services . 8
8.2 Process selection . 9
Annex A (informative) Process parameters .10
Annex B (informative) Characterization of a procedure set — Examples .13
Annex C (informative) Designating a processing category .29
Annex D (informative) Processing categories — Examples .31
Bibliography .49
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received. www.iso.org/patents
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
The committee responsible for this document is ISO/TC 198, Sterilization of health care products.
ISO 17665 consists of the following parts, under the general title Sterilization of health care
products — Moist heat:
— Part 1: Requirements for the development, validation and routine control of a sterilization process for
medical devices
— Part 2: Guidance on the application of ISO 17665 Part 1: 2006 [Technical Specification]
— Part 3: Guidance on the designation of a medical device to a product family and processing category for
steam sterilization [Technical Specification]
iv © ISO 2013 – All rights reserved

Introduction
The type of moist heat sterilization process used to successfully process a medical device is identified
from the physical, design, material and functional characteristics of the medical device and any sterile
barrier system and/or packaging system used to present the medical device for sterilization.
Manufacturers of moist heat sterilizers may supply sterilizers with a number of pre-set sterilization
processes. These pre-set sterilization processes may be suitable for sterilizing a wide range of medical
devices or combinations of medical devices; however, there may be a need to develop customized
sterilization processes to sterilize medical devices or combinations of medical devices that pose a
particular challenge to the pre-set sterilization processes.
The designs and nature of materials used to construct medical devices are increasing in complexity.
Materials used in the manufacture of sterile barrier systems and/or packaging systems and the
combinations of different medical devices in procedure sets can adversely affect conductivity, air
removal and moist heat penetration, causing a failure to obtain the required sterility assurance level.
The classification of a medical device into a product family can assist with the development of moist heat
sterilization process conditions for this medical device. Assigning a medical device to a particular product
family is the first stage of performance qualification at the point of use as specified in ISO 17665-1 and
ISO/TS 17665-2. The efficacy of sterilization for a medical device using the sterilization process for that
product family should be assessed and documented together with any pre-treatments, such as cleaning,
disinfection to reduce bioburden followed by lubrication and humidification of some materials e.g. those
containing cellulose.
In this part of ISO 17665 the attributes which relate to efficient sterilization and which are used to
identify a product family have been selected from operational experience, engineering considerations
and experimental data relating to the efficacy of the different types of moist heat sterilizers and their
sterilization processes, and the types and design of differing medical devices and sterile barrier
systems and/or packaging systems. Medical devices that are labelled by the manufacturer as being
capable of being sterilized via moist heat may be categorized into product families by a user. However,
not all medical devices will fit into one of the product families described in this part of ISO 17665. In
these cases, new product families will need to be identified based on the consideration of the products
attributes and require additional performance qualification.
Medical devices that have been classified into different product families are often processed in the same
sterilization load when assembled into a randomly selected load configuration. This approach is common
and acceptable in health care facilities where it is generally not feasible to qualify each sterilization load,
provided that the sterilization process and sterilizer have been shown to be capable of sterilizing the
range of product families constituting the sterilization load. Care should be taken to ensure that the
combination of product families does not create a greater sterilization challenge than that set by the
individual product families. In addition, consideration should be given to possible adverse interactions
between medical devices such as the contamination of instruments with textile fibres. The examples
shown in Annex B and D are illustrations of how the coding system is intended to be used in developing
a sterilizer load.
This part of ISO 17665 should be read in conjunction with ISO 17665-1 and ISO/TS 17665-2.
TECHNICAL SPECIFICATION ISO/TS 17665-3:2013(E)
Sterilization of health care products — Moist heat —
Part 3:
Guidance on the designation of a medical device to
a product family and processing category for steam
sterilization
1 Scope
This part of ISO 17665 provides guidance about the attributes of a medical device to be considered by
the user when assigning a medical device to a product family for the purpose of identifying and aligning
it to a processing category for a specific moist heat sterilization process.
NOTE While this part of ISO 17665 is applicable to health care facilities, it may be used by a manufacturer of
a sterile medical device and/or whenever information on reprocessing is required (see ISO 17664).
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 17665-1:2006, Sterilization of health care products — Moist heat — Part 1: Requirements for the
development, validation and routine control of a sterilization process for medical devices
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 17665-1 and the following apply.
3.1
master product
medical device or procedure set used to represent the most difficult to sterilize item in a product family
or processing category
3.2
processing category
collection of different products or product families that can be sterilized together
3.3
steam penetration resistance
challenge to a sterilization process from a medical device, including any sterile barrier/packaging
system that may delay attainment of the process parameters for moist heat sterilization on all parts of
the medical device
3.4
user
responsible body, which can be an individual or group, accountable for ensuring products are sterilized
and suitable for intended use
4 Classification
Each medical device, whether new or modified, should be classified using the general attributes listed
in Table 1. Specific characteristics of a medical device should, as applicable, be identified from the
subclauses detailed in 4.2.
NOTE 1 Requirements for information to be provided by the manufacturer for the reprocessing of resterilizable
medical devices are given in ISO 17664.
If a collection of medical devices are to be contained in a sterile barrier system and/or packaging system
e.g. a procedure set, the challenge to the sterilization process from each medical device should be rated
relative to the other medical devices as described in this part of ISO 17665. The product family assigned
to this collection should be determined by the medical device which presents the greatest challenge to
the sterilization process and the sterile barrier system and/or packaging system used. This product
family will enable an appropriate processing category and sterilization process to be selected. The
combination of the device with the highest rating and the chosen sterilization process should be subject
to qualification in accordance with ISO 17665-1.
NOTE 2 Requirements and guidance for sterile barrier systems and packaging systems may be found in
ISO 11607 (all parts) and EN 868 (all parts).
Some combinations of physical characteristics, such as those specified in Table 1, may cause an
unpredictable adverse change to the steam penetration resistance as illustrated in Table 6. This can
lead to an underestimation of the difficulty to sterilize (see Clause 5, Example 2). In such situations
performance qualification should always be carried out in accordance with ISO 17665-1.
4.1 General attributes
Table 1 — General attributes
Attribute Code
Design a
Weight b
Material c
Sterile barrier system d
4.2 Detailed attributes
The following attributes provide detail for characterizing a medical device and a sterilization process.
Increased resistance to steam penetration is indicated by ascending code numbers.
Some attributes will be specified by the manufacturer of the medical device and others by the user. The
manufacturer of a medical device will usually specify the attributes needed by the user to assess its
steam penetration resistance and to select a processing category for a specific sterilizer and sterilization
process. Both the resistance and the category should be reassessed when the medical device is to be
combined with others in a sterile barrier system and/or packaging system.
The sterilization process should be qualified to verify that the required lethality will be delivered to all
medical devices processed together (see ISO 17665-1 and ISO/TS 17665-2).
4.2.1 Design
For the purpose of identifying a type of sterilization process for reprocessing and assigning a processing
category, a medical device should be broadly identified from one or more of the designs described in
Table 2. The steam penetration resistance will be different for each design when air is to be removed and
replaced by saturated steam. The following should be considered when developing an air removal process.
2 © ISO 2013 – All rights reserved

a1: air is displaced predictably as temperature rises with the introduction of steam. This action is
unlikely to be affected by orientation.
a2: instrument may need to be in an open position and an active air removal process may be necessary.
a3: residual air in hollows may cause unpredictable delays to sterilizing conditions. Defined orientation
and/or the dilution of air by an active air removal process may be necessary.
a4: inadequate removal of air during the air removal stage of the sterilization process can cause
uncertainty in the attainment of sterilizing conditions.
a5: an active air removal process will be required. Condensate resulting from temperature differences
within materials, interaction between adjacent medical devices and the quality of steam can cause an
adverse effect on the efficiency of air dilution.
a6: an active air removal process will be required. Condensate can cause occlusion, inadequate air
removal and inadequate steam penetration.
a7: if an active air removal process is required, develop the sterilization process to the product.
Table 2 — Design
Structure Code Example
(a)
Solid, hollow 1 Bowl, jug, dish, bottle, chisel, single piece
skin retractor, single component empty
instrument tray
Pin and box joints 2 Scissor, forceps, needle holder
Lumen 3 Laparoscopic sheath, sucker, cannulated
reamer, rigid endoscope, cannulated screws
Porous 4 Linen, filters, gauze
Tubing, moving parts, 5 Power tool hose, silicone tubing, dental hand
tortuous paths piece, ear nose throat drill,
Lumen surrounded by a 6 Drill, cannulated screw driver, obturator,
large mass ratchet handle, bored handle
Other 7 Pre-filled syringe
4.2.2 Material
The materials used to manufacture a medical device will be either metallic or non-metallic or a
combination of both. Typically, metallic materials will have a high thermal conductivity and non-metals
will have low thermal conductivity.
Materials with low thermal conductivity exhibit higher temperature differences throughout the material
when compared to materials with high thermal conductivity. Both types of material present challenges
to the sterilization process. The moisture content of the material may also influence the heat transfer
into the product. This should be taken into account during performance qualification with the material
in its most challenging state.
When compared to materials with low thermal conductivity, materials with high thermal conductivity
and equal heat capacity will:
— initially generate more condensate in a given time period,
— absorb and release energy faster,
— attain a state of equilibrium faster.
Examples of some of the materials used are shown in Table 3.
Table 3 — Materials
Material Example material Code
(b)
Metal Stainless steel, carbon steel copper and copper- 1
based alloys. Other metals or combinations of
metal.
Non-metal Glass, cellulose, polycarbonate, PVC, PTFE, silicon. 2
Other non metals.
4.2.3 Weight
The weight of a medical device, or part of a medical device (if processed separately), or for a collection
of medical devices grouped into a single sterile barrier system and/or packaging system, should be
assigned to one of the codes indicated in Table 4. This information may be required when judging:
— heat-up time;
— cooling time/drying time;
— exposure time in a mixed weight sterilizer load;
— the stability of a single or composite construction material;
— the amount of condensate and its effect on steam penetration.
Table 4 — Weight
Weight Code
g (c)
Less than 50 1
50 to 499 2
500 to 1999 3
2000 and greater 4
4.2.4 Sterile barrier system and/or packaging system
Except when a medical device is to be presented aseptically immediately after being re-processed, it
will be contained in a sterile barrier system and/or packaging system prior to it being sterilized [see
ISO 11607 (all parts) for code d2 to d4 in Table 5]. When establishing the steam penetration resistance
and moisture retention for a medical device or a collection of medical devices, the influence on the
combined steam penetration resistance caused by the system and the materials used in its construction
should be known. A collection of sterile barrier systems and /or packaging systems are listed in Table 5.
NOTE 1 In some countries local regulations may forbid the sterilization of unwrapped medical devices, in
which case code d1 would not apply.
4 © ISO 2013 – All rights reserved

Table 5 — Sterile barrier system and/or packaging system
Sterile barrier system Code
(d)
None 1
Single wrapped/pouch 2
Double wrapped in wrapping material or 3
pouches, double wrapped container or tray,
reusable sterilization container according
to manufacturers instructions
Combination of two or more systems, for 4
example, a reusable sterilization container
with an inner sterile barrier system
NOTE 2 Information on the intended use of the sterile barrier systems will be available from the manufacturer.
The effect of combining two or more systems (d4) may require additional performance qualification (see
ISO 17665-1:2006, Clause 8).
5 Product family (pf)
The product family assigned to a medical device should be based on attributes identified from the ones shown
in 4.2. A number of product families that could be established from these attributes are listed in Table 6.
Use Table 6 to assign a product family to a medical device and then from this assignment identify the
steam penetration resistance. For each medical device:
— select a level for each attribute a to d;
— establish a match to one of the product families in the table;
— note the product family and then from column ‘e’, the estimate for steam penetration resistance;
— if a match cannot be obtained, establish a new one and then by comparison with established product
families and from performance qualification, estimate a steam penetration resistance.
A discussion and estimate for steam penetration resistance for three types of medical devices are shown
in 5.1, 5.2 and 5.3. A user may need to establish additional product families for those designs that cannot
be characterized into one of the seven designs illustrated in Table 2.
The steam penetration resistance assigned to each product family listed in Table 6 is estimated and
judged from the attributes identified in Clause 4. This estimation is first based on the design of the
medical devices in the family and then adjusted if influenced by the other attributes. A procedure set
will often contain a range of medical devices and components each assigned a different product family
and a different steam penetration resistance. The product family assigned to a procedure set should
normally align with the medical device or component assigned the highest steam penetration resistance
unless influenced by adjacent medical devices and/or components. Examples are illustrated in Annex B.
The actual steam penetration resistance will depend on the load configuration and any one of the following:
— design of the sterilizer;
— type of operating cycle;
— operational state of the sterilizer witnessed by validation and conformity to the requirements for
scheduled periodic tests;
— quality of services delivered to the equipment witnessed by test;
— site.
5.1 Example 1 — pf 1
A shallow, thin wall, metal bowl.
— design: a1,
— material: b1,
— weight: c1,
— sterile barrier system and/or packaging system: d1.
Steam condensing on the bowl will cause a higher concentration of air on its surfaces. This air will be
displaced by steam and sterilizing conditions will exist on its surface when the sterilization temperature
is measured at the reference measurement point e.g. the chamber drain.
Nominal changes to the non-condensable gases (NCG) in the steam and/or to air leakage into the
sterilizer chamber are unlikely to adversely affect the predicted efficiency of the sterilization process.
The estimated steam penetration resistance for this medical device is e1 (see Table 6) based on design
a1. The other attributes of the device will not affect this estimation.
5.2 Example 2 — pf 24
A length of thin wall soft plastic tubing.
— design: a5,
— material: b2,
— weight: c1,
— sterile barrier system and/or packaging system: d3.
Sterilization temperature measured at the reference measurement point may not be indicative of
sterilizing conditions within the tubing. The following should be considered when selecting a sterilization
process and loading configuration:
— an active air removal system is necessary;
— thin wall tubing is susceptible to kinking and collapse;
— occlusion caused by condensate will prevent the removal of air from within the tube and delay or
prevent the presence of sterilizing conditions;
— steam condensing on adjacent items can cause an increase in NCG local to the tube and this gas can
then be driven by the steam into the tubing;
— air leakage into the sterilizer chamber and/or increased NCG carried by the steam can add to
the air already in the tubing and this can then adversely affect the predicted efficiency of the
sterilization process.
The estimated steam penetration resistance according to design a5 will be e5. For this medical device,
the other attributes listed in Clause 4 will not affect this estimate.
Providing the above considerations are observed when selecting a sterilization process and loading
configuration, the estimated steam penetration resistance should remain at e5. However, due to the
number of variables listed above, steam penetration resistance may need to be judged from performance
qualification (see ISO 17665-1).
6 © ISO 2013 – All rights reserved

5.3 Example 3 — pf 27
Cannulated screw driver with a non-metallic or metallic coated handle.
— design: a6,
— material: b2,
— weight: c2,
— sterile barrier system and/or packaging system: d3.
Poor heat transfer through the surface of the handle will delay the presence of sterilizing conditions in
the lumen. This delay can vary for most of the reasons given in example 2.
The estimated steam penetration resistance based on design a6 will be e6. Weight and material may
affect this estimate.
Table 6 — Product families
MD Attribute Steam penetration
resistance
(estimated)
PF Design Material Weight Sterile barrier (e)
(a) (b) (c) system and/or
packaging
system
(d)
1 2 3 4 5 6 7 + 1 2 1 2 3 4 1 2 3 4 1 2 3 4 5 6 7 +
1 x x x x x x x
2 x x x x x
3 x x x x x x x
4 x x x x x
5 x x x x x x x
6 x x x x x x x
7 x x x x x x x x
8 x x x x x x x x x
9 x x x x x x x x x
10 x x x x x x
11 x x x x x x x x
12 x x x x x x x x
13 x x x x x x
14 x x x x x x
15 x x x x x x x
16 x x x x x
17 x x x x x x
18 x x x x x
19 x x x x x x x
20 x x x x x
21 x x x x x x x x
a
Special - sterilization process should be developed and qualified.
+ New product families that may be identified by the user.
Table 6 (continued)
MD Attribute Steam penetration
resistance
(estimated)
PF Design Material Weight Sterile barrier (e)
(a) (b) (c) system and/or
packaging
system
(d)
1 2 3 4 5 6 7 + 1 2 1 2 3 4 1 2 3 4 1 2 3 4 5 6 7 +
22 x x x x x x
23 x x x x x x x x
24 x x x x x x x x
25 x x x x x x x x
26 x x x x x x x x x
27 x x x x x x x x x
28 x x x x x x x x
a
29 x x x x
+
a
Special - sterilization process should be developed and qualified.
+ New product families that may be identified by the user.
6 Processing category
The medical devices included in a processing category should be based on product family and data that
establish the efficiency of a specific sterilizer and its sterilization process for the processing category.
Medical devices of widely different attributes combined in the same processing category can cause an
increase in the predicted steam penetration resistance. Based on the design of the individual instruments,
the penetration resistance for the general orthopaedic set described in B.4 would be e2. However, due to
the sterile barrier system, high total weight of the set, condensate collection, unpredictable air retention
and susceptibility to an increase in air leakage into the sterilizer chamber or to the non-condensable
gases contained in the steam, the steam penetration resistance for the general orthopaedic set is
estimated as e5. The effect on the efficiency of the sterilization process from such combinations and
changes should be known for each item contained in the processing category.
One example of how to designate a processing category for a number of procedure sets is illustrated
in Annex D.
7 Sterilization process parameters
The maximum values for the process parameters a medical device can be safely exposed to during a
moist heat sterilization process should not exceed those specified by the medical device manufacturer
(see Annex A).
8 Additional considerations
8.1 Services
Variations in the quality of the services used during the delivery of a sterilization process can affect the
efficiency of the sterilization process. Variations can also affect steam penetration resistance, levels of
contaminants and the shelf life of some of the medical devices subjected to the sterilization process. The
quality of the steam service should be as described in ISO/TS 17665-2:2009, A.11.2 and Table A.2.
8 © ISO 2013 – All rights reserved

8.2 Process selection
A sterilization process consists of a number of prescribed stages carried out in a controlled sequence.
The process variables and process parameters for each stage will define the type of medical device,
processing category and load configuration that can be sterilized. The first stage will be designed to
ensure that for a range of processing categories and load configurations, specified parts of each medical
device will be sterile after exposure in stage two of the sterilization process. Returning to atmospheric
conditions for use is carried out in the third stage.
In health care facilities, most medical devices are sterilized by saturated steam and the three stages
of a sterilization process are, sequentially, air removal, sterilizing and drying. The design for the air
removal stage will be based on the ease and way in which air can be removed from the surfaces of each
medical device in the sterilization load. A simple air removal system will be passive and rely on gravity
displacement of air resulting from the different densities of air and steam. This type of air removal
system is unsuitable if air can be trapped, such as in a packaging system or a lumen. The alternative to
gravity air removal is active air removal. Active air removal is achieved by using steam, vacuum pump
or pressurized water as a power source to generate a series of pressure changes which can be below
atmospheric pressure, above atmospheric pressure, or a combination of both. Upper and lower pressure
levels, the number of changes and the characteristics of each change will be based on the type of medical
device, the steam penetration resistance (see Table 6) and its processing category. Air removal should
ensure residual air in the sterilizer chamber and on the surfaces of the sterilizer load is insufficient to
affect the efficiency of sterilization.
Air leakage into the sterilizer chamber and non-condensable gases in the steam will adversely affect the
efficacy of the air removal stage. It can also be adversely affected if medical devices of widely differing
conductivity and/or weight are included in the same processing category.
Stage two will start at a specified minimum sterilizing temperature and exposure at this temperature
should be the minimum specified for the holding time. Additional exposure to allow for temperature
equilibration may be required when a high weight medical device is to be sterilized.
Stage three will be designed such that after the completion of drying, (normally by vacuum), filtered air
will restore the pressure in the sterilizer chamber to atmospheric pressure. The duration of the drying
stage will depend on the presentation and weight of each item of the sterilization load.
Annex A
(informative)
Process parameters
A.1 The critical process variables for a moist heat sterilization process are temperature, time and presence
of moisture (see ISO 17665-1). In order for a satisfactory process to be engineered other process parameters
will need to be considered such as pressure, rates of pressure and temperature change and dwell times.
A.2 A medical device should not be exposed to process parameters that can adversely affect functional
efficiency, therapeutic value and shelf life.
A.3 Process parameters used to ensure that a minimum sterility assurance is routinely obtained may
be determined from either a parametric or a biological approach as described in ISO/TS 17665-2:2009,
Annexes A and B respectively. Determining a process based on product bioburden considerations is
discussed in ISO 17665-1, 7.3 and 8.5.
A.4 The tests described in ISO/TS 17665-2, Annex A, are prescribed for a parametric approach and
are used to verify a minimum performance for a specific sterilizer. The data from these tests are used to
establish the process parameters listed in A.1 and A.2 and to confirm that air and non-condensable gas
remaining in a test load after the completion of the air removal stage will be insufficient to prevent the
presence of saturated steam on all the surfaces of the test piece, including concealed surfaces that are
open to the sterilizer chamber. The test piece and the performance requirements for these tests represent
a high steam penetration resistance (see Table 6). Figure A.1 illustrates a temperature profile for the small
load test (see ISO/TS 17665-2, Annex A).The difference in temperature between S and S can be used to
1 2
judge the presence of saturated steam.
If the sterilization process and the process parameters identified from these tests are to be used to
sterilize a medical device with a higher steam penetration resistance then data should be available to
justify this decision. The rationale for this decision should be documented.
10 © ISO 2013 – All rights reserved

Key
A start of plateau period
B end of plateau period
T sterilization temperature
s
T sterilization temperature band
B
S reference point
S centre of test piece
S 50mm above test piece
T maximum difference
T maximum difference – first 60s
T maximum difference – after 60s
t plateau period
t equilibration time
t 60s
t holding time
Figure A.1 — Performance requirements: Small load test
A.5 Medical devices that have similar steam penetration resistance but which are characterized by
attributes that are widely different may require exposure to dissimilar process parameters. If they are to
be included in the same processing category such as in a procedure set, process parameters according to
A.1 and A.2 should be verified.
A.6 While steam condensate remaining within a sterile barrier system may be used to identify a failure
of the sterilization process, it may also be indicative of additive influence on steam penetration resistance.
One or a combination of the following can be the cause:
— sterilizer chamber architecture;
— design and materials used to manufacture the sterile barrier system;
— load configuration;
— combination of high and low weight medical devices;
— water contained in the steam;
— operating cycle.
For some types of medical devices it may be necessary to include:
a) preheating prior to pressure changes for high weight devices;
b) delays between pressure changes to allow equalization of pressure and temperature in small
diameter lumens;
c) a high vacuum (e.g. 2kPa) prior to pressure changes to minimize the inclusion of water in open
ended tubing;
d) rate control for pressure changes to minimize crazing in thick walled plastic medical devices;
e) changes to the load configuration for a reduction in moisture retention.
12 © ISO 2013 – All rights reserved

Annex B
(informative)
Characterization of a procedure set — Examples
The following are examples and illustrate the combination of various medical devices in order to derive
product families.
B.1 Assessment/extraction set (oral)
B.1.1 General
The assessment/extraction set comprises a number of individual items as illustrated in Figure B.1,
detailed in Table B.2, and analysed in Table B.3. Assessment of the set is in accordance with Clause 4 and
is as follows.
— The design of the items in the set varies from simple to moderately complex. Item 8, (surgical suction
tip) has a lumen, a design classification of a3 and an estimated steam penetration resistance of e3,
the highest in the set.
— Materials used comprise both metal and plastic. The tray is made from polycarbonate, a material
that has a low thermal conductivity and deemed to present the greatest challenge. This material has
a classification b2 and an estimated steam penetration resistance e2.
— The average weight of the items is 25g. The total weight is 150g and classified as c2.
— Crepe paper wrap is used for the sterile barrier system. This has a classification of d3 and a steam
penetration resistance of e3.
Figure B.1 — Assessment/extraction set
Table B.2 — Content of assessment/extraction set
Item Description Quantity
1 Tray blue plastic 1
2 Tray liner 130 x 180cm 1
(not shown)
3 Mirror dental 1
4 Dental probe 1
5 Forceps 1
6 Syringe 1
7 Suction adaptor 1
8 Surgical suction tip 1
9 Tray tag 1
10 White crepe 60 x 60 2
(not shown)
Table B.3 — Analysis: assessment/extraction set
Attribute Description Code Steam
penetration
resistance
(estimated)
General A collection of solid instruments e3
description placed on to a liner in a plastic tray and
double wrapped, OR
e1
A similar collection of solid instru-
ments placed in a paper mache tray
and left unwrapped.
Total weight approximately 150g
Design Solid a1 e1
Perforated polycarbonate tray a2 e2
Lumen instrument (suction tip) a3 e3
Material Stainless steel b1 e1
Polycarbonate (tray) b2 e2
Weight Average 25g c1 e1
Sterile barrier None d1 e1
system and/
Crepe paper d3 e3
or packaging
system
B.1.2 Product family
The product family assigned to the assessment /extraction set is PF 8. Analysis of the set is illustrated
in Table B.4. The assignment of PF8 has been based on item 8 (see Table B.2) noting that the additive
influence from the polycarbonate tray and the low weight of adjacent medical devices in the set will be
insufficient to affect the estimated steam penetration resistance, e3 for this medical device.
14 © ISO 2013 – All rights reserved

Table B.4 — Product family — Classification based on estimates: Assessment/extraction set
MD Attribute Steam
penetration
resistance
(estimated)
PF Design Material Weight Sterile barrier (e)
(a) (b) (c) system and/
or packaging
system
(d)
1 2 3 4 5 6 7 + 1 2 1 2 3 4 1 2 3 4 1 2 3 4 5 6 7 +
8 x x x x x x x x x x
B.2 Cystoscope, bridge and tap set
B.2.1 General
The bridge and tap set comprises a number of individual items as illustrated in Figure B.2, detailed in
Table B.5, and analysed in Table B.6.
Assessment of the set is in accordance with Clause 4 and is as follows:
— the design of the items in the set varies from simple to complex. Item 3, (cystoscope-urethroscope
sheath) has a small lumen, a design classification a5 and an estimated steam penetration resistance
of e5, the highest in the set.
— materials used comprise both metal and plastic. The matting tray is made of silicone, has a low
thermal conductivity and deemed to present the greatest challenge. This material has a classification
b2 and an estimated steam penetration resistance a3.
— the total weight is 200g and the individual Items range in weight from 5g up to 100g. The
classification is c2.
— the sterile barrier system consists of a perforated aluminium tray and lid double wrapped in crepe
paper. This has a classification of d3 and a steam penetration resistance of e3.
Figure B.2 — Cystoscope, bridge and tap set (22 FG)
Table B.5 — Content of cystoscope, bridge and tap set (22 FG)
Item Description contents list Quantity
1 Sterilization tray 1
2 Silicone mat 1
3 Cystoscope- urethroscope sheath 1
4 Obturator 1
5 Stopcock for cystoscope-urethroscope 2
6 Spring cap 3
7 Telescope bridge 1
8 Stopcock for telescope bridge 1
9 Sealing cap 1
10 Tray tag (not shown) 1
11 White crepe 90 x 90 (not shown) 2
Table B.6 — Analysis: cystoscope, bridge and tap set (22 FG)
Attribute Description Code Steam
penetration
resistance
(estimated)
General description Rigid endoscope with parts, supported on silicone e5
mat, contained in a perforated container and lid and
double wrapped in crepe paper.
Total weight approximately 200 g
Design Solid a1 e1
Perforated aluminium tray a1 e1
Lumen a5 e5
Material Stainless steel, aluminium b1 e1
Silicone b2 e3
Weight 5 g to 100 g c1 e1
c2 e1
Sterile barrier system Crepe paper d3 e3
and/or packaging
system
B.2.2 Product family
The product family assigned to the cystoscope, bridge and tap set is PF24. Analysis of the set is
illustrated in Table B.7. The assignment of PF24 has been based on item 3 (see Table B.5) noting that the
additive influence from the silicone mat and the low weight of adjacent medical devices in the set will be
insufficient to affect the estimated steam penetration resistance, e5 for this medical device.
16 © ISO 2013 – All rights reserved

Table B.7 — Product family — Classification based on estimates: Cystoscope, bridge and tap set
(22 FG)
MD Attribute Steam
penetration
resistance
(estimated)
PF Design Material Weight Sterile barrier (e)
(a) (b) (c) system and/
or packaging
system
(d)
1 2 3 4 5 6 7 + 1 2 1 2 3 4 1 2 3 4 1 2 3 4 5 6 7 +
24 x x x x x x x x x x
B.3 Cataract ophthalmic No. 6 set
B.3.1 General
The cataract ophthalmic No. 6 set comprises a number of individual items as illustrated in Figure B.3,
detailed in Table B.8, and analysed in Table B.9.
Assessment of the set is in accordance with Clause 4 and is as follows.
— The design of items in the set comprise simple pin joints, box locks and solid construction. Items with
...