ISO 11138-1:1994

Sterilization of health care products — Biological indicators — Part 1: General

Specifies general production, labelling and performance requirements for the manufacture of biological indicators and suspensions intended for use in the validation and monitoring of sterilization cycles. Does not contain requirements for product directly inoculated with test organisms, or recovery procedures for such inoculated product.

Stérilisation des produits de santé — Indicateurs biologiques — Partie 1: Généralités

General Information

• Status: Withdrawn
• Publication Date: 05-Oct-1994
• Withdrawal Date: 05-Oct-1994
• ICS: 11.080.01 - Sterilization and disinfection in general
• Technical Committee: ISO/TC 198 - Sterilization of health care products
• Drafting Committee: ISO/TC 198/WG 4 - Biological indicators
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 26-Jun-2006

Relations

• Revised: ISO 11138-1:2006 - Sterilization of health care products — Biological indicators — Part 1: General requirements
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 11138-1
First edition
1994-10-01
Sterilization of health care products -
Biological indicators -
Part 1:
General
Stklisa tion des produits sanitaires - Indica teurs biologiques -
Partie 1: G&kralit&
Reference number
ISO 11138-1:1994( E)

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ISO 11138=1:1994(E)
Contents
Page
........................................... 1
1 Scope .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Normative references . . .a.
1
3 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~.‘.
2
4 Production, Performance and labelling requirements . . . . . . . . . . . . . . .
5 Determination of resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Annexes
A Determination of viable test organism count . . . . . . . . . . . . . . . . . . . . . . 8
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
B Survivor curve method
C Fraction negative analysis/MPN method for subsequent
determination of D value by Limited Spearman-Karber Method IO
D Calculation of D value using Limited Spearman-Karber
............................................ 11
procedure .
. . . . . . .*. 13
E Survival-kill response characteristics
F Determination of growth inhibition by carriers and primary packaging
. . . . . . . . . . . . . . . . . . . . . . . . . 14
materials exposed to sterilization processes
0 ISO 1994
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microfilm, without Permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-l 211 Geneve 20 e Switzerland
Printed in Switzerland

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0 ISO
ISO 11138=1:1994(E)
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. Esch 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.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 11138-1 was prepared by Technical Committee
lSO/TC 198, Sterilization of health care products.
ISO 11138 consists of the following Parts, under the general title
Ster-ilization of health care products - Biological indicators:
- Part 1: General
- Part 2: Biological indicators for ethylene Oxide sterilization
- Part 3: Biological indicators for mokt heat sterilization
Annexes A, B, C, D, E and F form an integral part of this patt of ISO 11138.

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0 ISO
ISO 11138=1:1994(E)
Introduction
This part of ISO 11138 specifies (see clause 1) general production, label-
ling and Performance requirements for the manufacture of biological indi-
cators intended for use as monitors of sterilization cycles. The procedures
and methods described should be carried out by suitably trained person-
nel.
Biological indicators are not intended for use in any process other than that
specified by the manufacturer on the labelling. The use of an inappropriate
biological indicator tan give misleading results.
Biological indicators should always be used in combination with physical
and/or Chemical monitoring in demonstrating the efficacy of a sterilizing
process. When a physico-Chemical variable of a sterilizing process is out-
side its specified limits, a sterilization cycle should always be regarded as
unsatisfactory, irrespective of the results obtained from biological indi-
cators.
The Performance of a biological indicator tan be affected by the conditions
of storage Prior to use, the methods of use or the techniques employed
after exposure to the process. For these reasons, the recommendations
of the manufacturer for storage and use should be followed and biological
indicators should be transferred to the specified recovery conditions as
soon as possible after exposure to the process. Biological indicators
should not be used beyond any expiry date stated by the manufacturer.
Biological indicators are used to test the effectiveness of sterilization
processes and equipment. These studies should be conducted by suitably
trained personnel.

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INTERNATIONAL STANDARD 0 ISO
ISO 11138=1:1994(E)
Sterilization of health care products - Biological
indicators -
Part 1:
General
ISO 8601: 1988, Data elemen ts and in terchange for-
1 Scope
mats - Information in terchange - Represen ta tion
of dates and times.
This part of ISO 11138 specifies general production,
labelling and Performance requirements for the
ISO 9002: 1994, Quality Systems - Model for quality
manufacture of biological indicators and suspensions
assurance in production, installation and servicing.
intended for use in the Validation and monitoring of
sterilization cycles.
ISO 11138-2: 1994, Sterilization of health care prod-
ucts - Biological indicators - Part 2: Biological indi-
NOTE 1 Subsequent Parts of ISO 11138 specify the par-
ca tors for ethylene Oxide steriliza tion.
ticular requirements for biological indicators for defined
sterilization processes.
ISO 11138-3: -l), Sterilization of health care products
- Biological indicators -
Part 3: Biological indica tors
This part of ISO 11138 does not contain requirements
for mois t hea t s teriliza tion.
for product directly inoculated with test organisms,
or recovery procedures for such inoculated product.
Nor does it specify requirements for biological indi-
cators that use more than one strain or species of
microorganism on a carrier.
3 Definitions
For the purposes of all Parts of ISO 11138, the fol-
lowing definitions apply.
3.1 biological indicator; BI: Inoculated carrier con-
2 Normative references
tained within its primary pack ready for use and pro-
viding a defined resistance to the specified
The following Standards contain provisions which,
sterilization process.
through reference in this text, constitute provisions
of this part of ISO 11138. At the time of publication,
3.2 carrier: Supporting material on which test
the editions indicated were valid. All Standards are
organisms are deposited.
subject to revision, and Parties to agreements based
on this part of ISO 11138 are encouraged to investi-
gate the possibility of applying the most recent edi- 3.3 primary pack: System which protects the in-
oculated carrier from darnage and contamination
tions of the Standards indicated below. Members of
IEC and ISO maintain registers of currently valid without preventing Penetration of the sterilizing
International Standards. agent(s).
1) To be published.

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ISO 11138=1:1994(E) 0 ISO
3.4 secondary pack: Container System in which 3.14 colony-forming unit (CFU): Visible growth of
biological indicators are packed for transport and microorganisms arising from a Single cell or multiple
storage. cells.
3.15 self-contained biological indicator: Biological
35 . inocu lated carrier: Carrie r on which a def ined
indicator presented in such a way that the primary
num ber of test organisms have been depos ited.
pack, intended for incubation, contains the growth
medium required for recovery.
36 . test nism: Microorgani sm used for the
orga
man
ufactu re of inocula ted carriers.
3.16 survival-kill window: Extent of exposure to a
sterilization process under defined conditions when
3.7 viable test organism count: Number of viable
there is a transition from all biological indicators
test organisms in a unit volume of a Suspension or on
showing growth (survival exposure) to all biological
an inoculated carrier, estimated by growth of discrete
indicators showing no growth (kill exposure).
colonies under the stated culture conditions.
3.17 nominal population: Stated number of
3.8 inactivation: Loss of the ability of the test
microorganisms.
organisms to germinate, outgrow and/or multiply un-
der the specified culture conditions.
NOTE 5 The actual number of microorganisms will differ
from the nominal population of microorganism as a result
of the accuracy of the inoculation and recovery methods.
3.9 culture conditions: Manufacturer’s stated
combination of conditions including the growth me-
3.18 resistometer: Equipment designed to create
dium with the period and temperature of incubation,
defined combinations of the physico-Chemical vari-
used to promote germination, outgrowth and/or mul-
ables of a sterilization process within defined Iimits.
tiplication of the test organism.
3.10 recognized culture collection: International
4 Production, Performance and labelling
depository authority under the Budapest Treaty on the
requirements
International Recognition of the Deposit of
Microorganisms for the Purpose of Patent and Regu-
4.1 Manufacturing controls and quality
lation.
Systems
3.11 D value; Decimal reduction value: Exposure
4.1 .l All operations required by this part of
time or absorbed radiation dose required to secure
ISO 11138 shall be controlled according to a quality
inactivation of 90 % of a population of test organisms
System complying with the requirements of
under stated conditions.
ISO 9002.
3.12 survivor curve: Graphical representation of in-
4.1.2 Traceability of manufacturing components
activation against increasing exposure to stated con-
shall be maintained.
ditions.
Manufacturing components should include all ma-
3.13 process challenge device: Object which
terials and components incorporated in or coming into
simulates the worst case of conditions as they are
direct contact with the test organism Suspension, the
given for the sterilizing agent(s) in the items of the
inoculated carrier or the biological indicator.
goods to be sterilized.
4.1.3 The finished product supplied by the manu-
NOTES
facturer (Suspension, inoculated carrier or biological
indicators) shall have no organisms, other than the
2 The process challenge device is so constituted that a
test organism, present in sufficient numbers to impair
biological indicator tan be arranged in the place most diffi-
the Utility of the product. This shall be validated,
cult for the sterilizing agent(s) to resch.
controlled, monitored and recorded, during pro-
3 The design of the process challenge device depends on duction.
the kind of goods to be sterilized and the sterilization pro-
cedure. The biological indicator should not interfere with the
4.2 Test organisms
function of the test body.
4.2.1 Test organisms shall be of a strain suitable for
4 In some process challenge devices an inoculated carrier
may be used instead of a biolo Igical indica tor. handling without special containment facilities.
2

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0 ISO
ISO 11138~1:1994(E)
4.2.2 Test organisms shall be of a defined strain, 4.3.4 If a test organism Suspension is distributed for
lodged with a recognized culture collection, and shall use in the preparation of inoculated carriers or the
be unambiguously identified by reference to the cul- preparation of inoculated product, then each Container
ture collection number. of test organism Suspension shall be accompanied by
the following information:
4.2.3 When the strain of the test organism to be
a) the name of the test organism;
used is not lodged with a recognized culture col-
lection, the manufacturer shall be responsible for
b) the name or abbreviation of the culture collection
lodging that particular strain with a recognized culture
from which the test organism has been obtained
collection.
and the reference number of the species;
4.2.4 The originating inoculum for each batch of test
c) the nominal volume of Suspension, in millilitres (or
organism Suspension shall be
in grams, if not a Suspension);
a) traceable to the reference culture lodged with the
d) a unique code by which the manufacturing history
recognized culture collection; and
tan be traced;
b) verified as to its identity and purity.
e) the viable count in test organisms per millilitre;
The method(s) used for the maintenance of cultures
f) the recommended storage conditions;
of the test organism should be designed and main-
tained to ensure that the cultures are protected from
g) the expiry date or shelf life, expressed in accord-
contamination and induced changes in their inherent
ante with ISO 8601 (i.e.YY-MM-DD);
properties.
h) the manufacturer’s name, trade mark, address or
Verification tests are specific for each strain of test
0th er means of identification; an d
organism and should be documented and validated
by the manufacturer.
i) disposal instructions.
4.3 Test organism suspensions
4.3.5 When requested by the purchaser, the manu-
4.3.1 The culture medium and incubation conditions
facturer shall supply details of the resistance and
used for preparation of the test organism Suspension
Performance characteristics of the Suspension. These
shall be defined by the manufacturer. These con-
data shall be determined by a method agreed upon
ditions shall consistently produce test organism sus-
by the purchaser and manufacturer.
pensions that meet the Performance requirements of
this part of ISO 11138 and the particular Performance
requirements provided in ISO 11138-2 and
4.3.6 The conditions for storage of suspensions of
ISO 11138-3, as appropriate.
test organisms and their expiry date shall be defined
by the manufacturer. These conditions shall be moni-
4.3.2 The method of harvesting and subsequent
tored during storage. These conditions shall maintain
treatment shall ensure that the Suspension to be used
the test organism suspensions so that they continue ’
in the inoculation of carriers is free from residues of
to meet the Performance requirements of this part of
the culture medium which could adversely influence
ISO 11138 and the particular Performance require-
the Performance of the inoculated carrier or biological
ments provided in ISO 11138-2 and ISO 11138-3, as
indicator.
appropriate.
This shall not be required where the manufacturer has
demonstrated that residues of the culture medium do
not adversely influence the Performance of the in-
4.3.7 The viable test organism count of the suspen-
oculated carrier or biological indicator.
sion shall be determined.
Where the user requires information on the growth
4.3.3 Manufacturers of test organism suspensions
and/or biological indicators shall maintain adequate index of the test organism, this should be determined
records in Order to allow traceability of biological indi- by expressing the viable test organism count as a
cators and test organism Suspension back to the cul- percentage of the total count determined microscopi-
ture obtained from the culture collection. cally.

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ISO 11138-1:1994(E)
4.3.8 The manufacturer shall ensure that transport
4.5 Inoculated carriers
to a third Party is carried out under controlled con-
ditions compatible with the storage conditions speci-
4.5.1 In the preparation of a batch of inoculated car-
fied for the Suspension of test organisms (see 4.3.6).
riers, only one strain of a species of test organism
shall be used.
4.4 Carrier, primary packaging and design
4.5.2 Inoculated carriers shall be prepared by inocu-
lating carriers with test organism Suspension, fol-
lowed by drying under controlled conditions.
4.4.1 Carriers and primary packaging shall not con-
tain any contamination (physical, Chemical or
4.5.3 The conditions under which inoculation is car-
microbial) that would adversely affect the perform-
ried out shall be specified, validated and controlled to
ante of the biological indicator.
ensure that the inoculated carrier remains free from
microorganisms, other than the test organism, which
may affect adversely the Performance of the product
4.4.2 The carrier and primary packaging shall not be
as specified in ISO 11138-2 and ISO 11138-3, as ap-
degraded by the sterilization process with which it is
propriate.
intended to be used in such a way that the perform-
ante characteristics of the inoculated carrier are ad-
versely affected.
4.5.4 The same nominal population of test
organisms shall be deposited on each inoculated car-
The carrier should withstand transport in the primary
rier used in the manufacture of a batch of biological
and secondary pack and handling at the Point of use
indicators.
without breakage.
4.5.5 The conditions for storage of inoculated car-
The design of the carrier and/or Primat-y pack should
riers and their expiry date shall be defined by the
be such that
manufacturer. These conditions shall be monitored
during storage. These conditions shall maintain con-
a) it will minimize the loss of the original inoculum
sistently the Performance requirements of this patt
of test organisms during transport and handling,
of ISO 11138 and the particular Performance require-
and during shelf life;
ments for inoculated carriers in ISO 11138-2 and
ISO 11138-3, as appropriate.
b) it is appropriate for use as part of a process chal-
lenge device.
4.5.6 Where the inoculated carriers are packaged for
conversion into biological indicators, they shall be
4.4.3 Compliance with 4.4.2 shall be tested by ob-
packed in a manner that does not affect the nominal
servation of carrier and primary packaging exposed to
of individual inoculated
population or Performance
extreme ranges and rates of Change of Chemical and
carriers.
physical variables of the sterilization process.
4.5.7 Esch batch of inocu ated carriers shall be ac-
NOTE 6 These Iimits are given in the relevant subse-
companied by the following information:
quent Parts of ISO 11138.
“inoculated carriers”;
d
4.4.4 During and after the sterilization process, the
W the name of the test organrsm;
carrier and primary package shall neither retain nor
release any substance to such an extent that, on
c) directions for use, especially data about the me-
transfer to the growth medium, under the culture
dium and conditions to be used for recovery of
conditions, there will be inhibition of the growth of
test organisms after exposure to the sterilization
low numbers of surviving test organisms.
process;
Tests for compliance with this requirement shall be
d) the name of the culture collection from which the
performed in accordance with annex F.
test organism has been obtained and the refer-
ence number of the species;
4.4.5 The manufacturer shall provide the purchaser
with a Statement of the maximum and the minimum e) the number of test organisms per inoculated car-
values of each dimension of the carrier on request.
4

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0 ISO
ISO 11138=1:1994(E)
f) the batch number or unique code by which the 4.6.5 The Primar-y pack shall be validated for its in-
tended use.
manufacturing history tan be traced;
Appropriate I nternation al Standards or national stan-
g) data about the resistance characteristics of the
dards should be used.
inoculated carriers to the sterilization process for
which they are suitable, including the test con-
ditions and methods used to determine these
4.6.6 Esch biological indicator Primat-y package shall
characteristics;
be labelled with the following information:
h) the number of inoculated carriers in the secondary
a) the name of the test organism;
pack;
the batch number of the biological indicator;
b)
the recommended storage conditions;
i)
c) the expiry date of the biological indicator, ex-
j) the expiry date of the inoculated carriers, ex-
pressed in accordance with ISO 8601 (i.e.
pressed in accordance with ISO 8601 (i.e.
YY-M M-DD);
YY-M M-DD);
d) an indication of the sterilization process for which
the manufacturer’s name, trademark, address or
kl
the biological indicator is suitable; and
other means of identification;
e) the manufacturer’s name, trademark, address or
1) the sterilization process for which the inoculated
other means of identification.
carriers are suitable; and
m) disposal instructions.
4.6.7 Biological indicators shall be packed in a sec-
ondary pack for transport and storage.
4.6 Biological indicators 4.6.8 The secondary pack shall be labelled with the
following information:
” biological indicators”;
4.6.1 Biological indicators shall be prepared by a)
packaging individual inoculated carriers in a primary
b) the information specified in 4.6.6;
pack.
c) the name of the culture collection from which the
test organism has been obtained and the refer-
4.6.2 The primary packaging shall be designed, con-
ence number of the species;
structed and validated to ensure that the biological
indicator presented in the Primat-y packaging meets
d) the number of test organisms on each biological
the Performance requirements of ISO 11138-2 and
indicator as determined for the batch of inoculated
ISO 11138-3, as appropriate.
carriers;
e) the number of biological indicat
...