SIST EN 113-2:2021
(Main)Durability of wood and wood-based products - Test method against wood destroying basidiomycetes - Part 2: Assessment of inherent or enhanced durability
Durability of wood and wood-based products - Test method against wood destroying basidiomycetes - Part 2: Assessment of inherent or enhanced durability
This document specifies a method of test for determining the natural durability of a timber against wood-destroying basidiomycetes cultured on a malt extract agar medium. The method is applicable to all timber species.
Furthermore this method can be used to test modified wood. The test method described in this document can be applied to specific wood species, commercial supplies of sawn timber, wood-based materials, wood treated with preservatives and modified wood, both thermally and chemically modified wood.
However, this document is not intended to determine the effectiveness of wood preservatives used to prevent decay.
NOTE 1 Determining the efficacy of wood preservatives used to prevent decay is the scope of EN 113-1. However, in addition to this and with some amendments, it might also be possible in some cases to test treated wood using the method described here.
NOTE 2 This method can be used in conjunction with an ageing procedure, for example EN 73 or EN 84.
Annex A (informative) contains a guidance on sampling.
Annex B (normative) contains some methods of sterilization.
Annex C (informative) contains information on the culture vessels.
Annex D (informative) contains an example of a test report.
Annex E (informative) contains information on the test fungi.
Annex F (informative) contains the assessment of the results.
Dauerhaftigkeit von Holz und Holzprodukten - Prüfverfahren in Bezug auf Holz zerstörende Basidiomyceten - Teil 2: Bewertung der natürlichen oder verbesserten Dauerhaftigkeit
Dieses Dokument legt ein Prüfverfahren zur Bestimmung der natürlichen Dauerhaftigkeit einer Holzart gegen Holz zerstörende Basidiomyceten fest, die auf einem Agar Medium gezüchtet wurden. Das Verfahren ist auf alle Holzarten anwendbar.
Zudem kann dieses Verfahren auch bei modifiziertem oder behandeltem Holz angewendet werden. Das in diesem Teil 2 von EN 113 beschriebene Prüfverfahren ist auf spezifische Holzarten, handelsübliches Schnittholz, Holzprodukte, mit Schutzmitteln behandeltes Holz und modifiziertes Holz einschließlich wärmebehandeltem Holz anwendbar. Diese Norm dient jedoch nicht dazu, die Wirksamkeit von Holzschutzmitteln, die zur Fäulnisverhinderung eingesetzt werden, zu bestimmen.
ANMERKUNG 1 Die Bestimmung der Wirksamkeit von Holzschutzmitteln, die zur Fäulnisverhinderung eingesetzt werden, gehört zum Anwendungsbereich von EN 113-1.
ANMERKUNG 2 Dieses Verfahren kann in Zusammenhang mit einer Alterungsbeanspruchung angewendet werden, z. B. nach EN 73 oder EN 84.
Anhang A (informativ) enthält eine Anleitung zur Probenahme.
Anhang B (informativ) enthält einige Sterilisationsverfahren.
Anhang C (informativ) enthält Informationen zu den Prüfgefäßen.
Anhang D (informativ) enthält ein Beispiel für einen Prüfbericht.
Anhang E (informativ) enthält Informationen zu den Prüfpilzen.
Anhang F (informativ) enthält die Bewertung der Ergebnisse.
Durabilité du bois et des matériaux dérivés du bois - Méthode d'essai vis-à-vis des champignons basidiomycètes - Partie 2 : Détermination de la durabilité inhérente ou améliorée
Le présent document décrit une méthode d'essai permettant de déterminer la durabilité naturelle d'un bois vis-à-vis des champignons basidiomycètes lignivores cultivés sur milieu malt-agar. La méthode est applicable à toutes les essences de bois.
En outre, cette méthode peut être utilisée pour soumettre à essai le bois modifié ou traité. La méthode d'essai décrite dans la présente seconde partie de l'EN 113 peut être appliquée à des essences spécifiques de bois, aux approvisionnements commerciaux en bois scié, aux matériaux à base de bois, aux bois traités par produit de préservation et aux bois modifiés y compris par traitement thermique. Cependant, la présente norme n'a pas pour vocation de déterminer l'efficacité d'un produit de préservation du bois utilisé pour empêcher la dégradation fongique.
NOTE 1 La détermination de l'efficacité d'un produit de préservation du bois empêchant la dégradation fongique relève du domaine d'application de l'EN 113-1.
NOTE 2 Cette méthode peut être utilisée conjointement avec une épreuve de vieillissement, par exemple selon l'EN 73 ou l'EN 84.
L'Annexe A (informative) donne des recommandations relatives à l'échantillonnage.
L'Annexe B (informative) donne plusieurs méthodes de stérilisation.
L'Annexe C (informative) donne des informations sur les flacons d'essai.
L'Annexe D (informative) donne un exemple de rapport d'essai.
L'Annexe E (informative) donne des informations sur les champignons d'essai.
L'Annexe F (informative) décrit l'évaluation des résultats.
Trajnost lesa in lesnih proizvodov - Preskusna metoda proti glivam prostotrosnicam - 2. del: Ocenjevanje naravne ali izboljšane odpornosti
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 113-2:2021
01-marec-2021
Nadomešča:
SIST EN 113:2002
SIST EN 113:2002/A1:2004
SIST-TS CEN/TS 15083-1:2006
Trajnost lesa in lesnih proizvodov - Preskusna metoda proti glivam
prostotrosnicam - 2. del: Ocenjevanje naravne ali izboljšane odpornosti
Durability of wood and wood-based products - Test method against wood destroying
basidiomycetes - Part 2: Assessment of inherent or enhanced durability
Dauerhaftigkeit von Holz und Holzprodukten - Prüfverfahren in Bezug auf Holz
zerstörende Basidiomyceten - Teil 2: Bewertung der natürlichen oder verbesserten
Dauerhaftigkeit
Durabilité du bois et des matériaux dérivés du bois - Méthode d'essai vis-à-vis des
champignons basidiomycètes - Partie 2 : Détermination de la durabilité inhérente ou
améliorée
Ta slovenski standard je istoveten z: EN 113-2:2020
ICS:
71.100.50 Kemikalije za zaščito lesa Wood-protecting chemicals
SIST EN 113-2:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 113-2:2021
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SIST EN 113-2:2021
EN 113-2
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2020
EUROPÄISCHE NORM
ICS 71.100.50 Supersedes CEN/TS 15083-1:2005, EN 113:1996
English Version
Durability of wood and wood-based products - Test
method against wood destroying basidiomycetes - Part 2:
Assessment of inherent or enhanced durability
Durabilité du bois et des matériaux dérivés du bois - Dauerhaftigkeit von Holz und Holzprodukten -
Méthode d'essai vis-à-vis des champignons Prüfverfahren gegen Holz zerstörende Basidiomyceten
basidiomycètes - Partie 2 : Détermination de la - Teil 2: Bewertung der natürlichen oder verbesserten
durabilité inhérente ou améliorée Dauerhaftigkeit
This European Standard was approved by CEN on 2 November 2020.
CEN 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. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 113-2:2020 E
worldwide for CEN national Members.
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EN 113-2:2020 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Principle . 6
5 Test material and apparatus . 7
5.1 Biological material . 7
5.1.1 Test fungi . 7
5.1.2 Wood as virulence control . 8
5.2 Products and reagents . 9
5.3 Apparatus . 9
5.3.1 Culture vessels . 9
5.3.2 Drying oven . 9
5.3.3 Desiccators . 9
5.3.4 Conditioning chamber . 9
5.3.5 Culture chamber . 9
5.3.6 Test specimens supports . 9
5.3.7 Equipment for steam sterilization or access to a radiation source . 10
5.3.8 Ordinary laboratory equipment . 10
6 Test specimens . 10
6.1 Species and source of wood . 10
6.2 Wood quality . 10
6.3 Provision of the test specimens . 10
6.4 Dimensions of test specimens . 11
6.5 Number and distribution of test specimens . 11
7 Procedure. 12
7.1 Preparation of the wood test specimens . 12
7.1.1 Virulence control . 12
7.1.2 Wood under test . 12
7.2 Exposure to fungi . 13
7.3 Culture conditions and duration of test . 13
7.4 Assessment of test . 13
7.4.1 Examination of the test specimens . 13
7.4.2 Validity of results . 14
7.4.3 Assessment of results . 14
8 Statement of results . 14
9 Test report . 15
Annex A (informative) Guidance on sampling . 16
Annex B (normative) Methods of sterilization . 18
Annex C (informative) Culture vessels . 19
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Annex D (informative) Example of a test report. 22
Annex E (informative) Test fungi . 23
Annex F (informative) Assessment of results . 27
Bibliography . 29
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EN 113-2:2020 (E)
European foreword
This document (EN 113-2:2020) has been prepared by Technical Committee CEN/TC 38 “Durability of
wood and wood-based products”, the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by May 2021, and conflicting national standards shall be
withdrawn at the latest by May 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes CEN/TS 15083-1:2005, EN 113:1996, EN 113:1996/A1:2004.
The different parts of EN 113 deal with similar testing but relate to a different scope.
In comparison with CEN/TS 15083-1:2005 EN 113:1996, EN 113:1996/A1:2004, the following
significant changes have been made:
— change of the title;
— the obligatory fungi are indicated differently;
— the methods for sterilization are updated;
— all annexes are informative except Annex B.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North
Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
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EN 113-2:2020 (E)
Introduction
This document describes a laboratory method of test which gives a basis for the assessment of the
biological durability of a sample of wood or wood product against attack by wood-destroying
basidiomycetes. Specifically the natural durability of a wood species can vary depending on the
conditions of growth such as climate and soil type. For this reason, the durability established using the
method described in this document will relate only to the sample of timber tested. Guidance on sampling
is given in Annex A.
This laboratory method provides one criterion by which the durability of the timber can be assessed. It
is recommended that this information is supplemented by data from other relevant tests, and above all
by practical experience.
The procedures described in this standard method are intended to be carried out by suitably trained or
supervised specialists.
5
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1 Scope
This document specifies a method of test for determining the natural durability of a timber against wood-
destroying basidiomycetes cultured on a malt extract agar medium. The method is applicable to all timber
species.
Furthermore this method can be used to test modified wood. The test method described in this document
can be applied to specific wood species, commercial supplies of sawn timber, wood-based materials,
wood treated with preservatives and modified wood, both thermally and chemically modified wood.
However, this document is not intended to determine the effectiveness of wood preservatives used to
prevent decay.
NOTE 1 Determining the efficacy of wood preservatives used to prevent decay is the scope of EN 113-1. However,
in addition to this and with some amendments, it might also be possible in some cases to test treated wood using
the method described here.
NOTE 2 This method can be used in conjunction with an ageing procedure, for example EN 73 or EN 84.
Annex A (informative) contains a guidance on sampling.
Annex B (normative) contains some methods of sterilization.
Annex C (informative) contains information on the culture vessels.
Annex D (informative) contains an example of a test report.
Annex E (informative) contains information on the test fungi.
Annex F (informative) contains the assessment of the results.
2 Normative references
There are no normative references in this document.
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 https://www.iso.org/obp
3.1
supplier
sponsor of the test, person or company providing the sample of wood/timber to be tested
4 Principle
Test specimens of the timber under test and reference timber test specimens are exposed to attack by
pure cultures of basidiomycetes. After a prescribed period of incubation under defined conditions, the
percentage loss in dry mass of the test specimens is used to establish the timber durability classification
of the timber under test.
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5 Test material and apparatus
5.1 Biological material
5.1.1 Test fungi
5.1.1.1 General
The test fungi to be used are as follows and relate to corresponding virulence control specimens.
It is required that the reference timber virulence control specimens provide a median mass loss of at least
30 % with one of the test fungi (see also 5.1.2.5 and 7.4.2).
NOTE Besides obligatory fungi also other test fungi can be used (see Annex E).
5.1.1.2 Test fungi for hardwoods with beech as virulence control wood
Obligatory fungi:
— Coniophora puteana (Schumacher ex Fries) Karsten (BAM Ebw. 15).
Loss in mass of beech in 16 weeks: minimum 20 %.
— Trametes versicolor (L.) Lloyd (CTB 863A).
Loss in mass of beech in 16 weeks: minimum 20 %.
5.1.1.3 Test fungi for softwoods with Scots pine sapwood as virulence control wood
Obligatory fungi
— Coniophora puteana (Schumacher ex Fries) Karsten (BAM Ebw. 15).
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
— Rhodonia placenta (Fr.) Niemelä, K.H. Larss. and Schigel (FPRL 280).
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
5.1.1.4 Test fungi for modified wood with both beech and Scots pine sapwood as virulence
control wood
Obligatory fungi:
— Coniophora puteana (Schumacher ex Fries) Karsten (BAM Ebw. 15) for both softwoods and
hardwoods
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
Loss in mass of beech in 16 weeks: minimum 20 %.
— Rhodonia placenta (Fr.) Niemelä, K.H. Larss. and Schigel (FPRL 280) for softwoods.
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
— Trametes versicolor (L.) Lloyd (CTB 863A) for hardwoods.
Loss in mass of beech in 16 weeks: minimum 20 %.
5.1.1.5 Maintenance of fungal strains
The strains shall be maintained and treated so that its virulence is conserved and ensured (see Annex E).
7
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The strains shall be maintained and treated (frequency of subculturing, alternation of culture media, etc.)
in accordance with the instructions of their laboratory of origin (see E.2).
NOTE The parent strain is maintained in the laboratory of its origin so as to conserve and to ensure its vigour.
If tests are not undertaken regularly or if a strain shows signs of degeneration a new standard culture of
the strain should be obtained from the laboratory of its origin for each test (see E.2).
When new strains are received, the virulence shall be tested to ensure the strain can achieve the
minimum loss in mass (see 5.1.1.2 and 5.1.1.3).
5.1.2 Wood as virulence control
5.1.2.1 Species used for the tests
— Scots pine sapwood (Pinus sylvestris Linnaeus) for tests with softwoods;
— Beech (Fagus sylvatica Linnaeus) for tests with hardwoods;
— For modified wood both Scots pine sapwood and beech should be used.
5.1.2.2 Wood quality
The wood shall be free from cracks, stain, decay, insect damage or other defects. The wood shall not have
been water-stored, floated, chemically treated or steamed.
NOTE Wood that has been kiln dried at temperatures not above 60 °C can be used.
The Scots pine shall be exclusively sapwood containing little resin and having between 2,5 and 8 annual
growth rings per 10 mm. The proportion of latewood in the annual rings shall not exceed 30 % of the
whole.
The beech shall be even-grained, free from tyloses, discolouration and red heart. It shall have between 2
and 6 annual growth rings per 10 mm.
5.1.2.3 Provision of virulence control specimens
Prepare planed strips having a cross-section of (25 ± 0,5) mm x (15 ± 0,5) mm. The longitudinal faces
shall be parallel to the direction of the grain. The annual rings shall not be parallel to the broad faces
(contact angle to be greater than 5°) but otherwise may run in any direction. Make transverse cuts, neatly
to give sharp edges and a fine-sawn finish to the end-grain surfaces, to give virulence control specimens
(50 ± 0,5) mm long.
The virulence control specimens shall originate from a minimum of three trees or shall be taken at
random from a stock originally of more than 500 test specimens and originating from at least five planks.
5.1.2.4 Dimensions and density of virulence control specimens
The dimensions of each reference timber virulence control specimen at (12 ± 2) % moisture content or
conditioned at (65 ± 5) % RH and (20 ± 2) °C for at least 2 weeks, shall be (50 ± 0,5) mm
x (25 ± 0,5) mm x (15 ± 0,5) mm.
NOTE A two-prong electrical conductivity moisture meter is suitable for assessing moisture content.
In a batch of virulence control specimens, the density of an individual is permitted to differ from the mean
value of the batch by ± 10 %.
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5.1.2.5 Number and distribution of virulence control specimens
Use at least 10 reference timber virulence control specimens for each test fungus. Mark each reference
timber virulence control specimen so that it can be identified throughout the test.
5.2 Products and reagents
The culture medium shall be a malt agar medium with the following composition:
— malt extract: in concentrated form: (50 ± 0,5) g; in powder form: (40 ± 0,5) g;
— agar causing no inhibition of growth of fungi: (20 ± 0,5) g to (30 ± 0,5) g;
— de-ionized water; quantity to make up to 1000 g.
Preferably use water conforming to grade 3 of ISO 3696.
Prepare this medium by warming the mixture in a boiling water bath or steam bath, stirring until
completely dissolved.
Place in each culture vessel (5.3.1) a sufficient quantity of the medium to provide a minimum depth of
3 mm to 4 mm when in its in-use position. Close the vessels as specified in 5.3.1 and sterilize in an
autoclave at 121 °C for 20 min. Let the vessels cool in their in-use position.
5.3 Apparatus
5.3.1 Culture vessels
Kolle flasks or equivalent vessels with a capacity of between 400 ml and 650 ml providing a flat surface
2 2
area of between 85 cm and 120 cm for the medium and close with a material that allows for air
exchange.
NOTE 1 Examples of suitable vessels are given in Annex C.
NOTE 2 Kolle flasks are usually plugged with a wad of cotton wool. Other culture vessels are usually fitted with
leakproof lids, the centres of which are pierced with a round hole of up to 15 mm diameter and plugged with a wad
of cotton wool.
5.3.2 Drying oven
Capable of being controlled at (103 ± 2) °C.
5.3.3 Desiccators
With efficient desiccant (silica gel for example).
5.3.4 Conditioning chamber
Well ventilated and controlled at (20 ± 2) °C and (65 ± 5) % relative humidity.
5.3.5 Culture chamber
Incubator or room, dark and controlled at (22 ± 2) °C and (70 ± 5) % relative humidity.
5.3.6 Test specimens supports
Made of glass, stainless steel or any other inert material, that is to say, with no risk of having any effect
on the culture medium, the fungus, the wood, or of modifying itself. The supports are used to prevent
direct contact of the specimens with the culture medium, but shall not separate them from it by more
than 3 mm.
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If abnormally high moisture contents (see 7.4.1) are experienced consistently, use of specimen supports
of approximately 5 mm thick could help to control the problem. If thicker specimen supports are used,
this should be recorded in the test report. Abnormally high moisture contents are those values of final
moisture content that are a mass fraction greater than 100 %.
NOTE Supports might be capable of holding either one or two test specimens.
5.3.7 Equipment for steam sterilization or access to a radiation source
See Annex B.
5.3.8 Ordinary laboratory equipment
Including a balance capable of weighing to an accuracy of 0,01 g.
6 Test specimens
6.1 Species and source of wood
Ensure that the species of each plank or log to be tested has been identified correctly and record both the
botanical and the trade name. Obtain as much information as possible on the origin and history of the
sample (see Annex A). The sample of timber shall be free from penetrating wood preservative treatments,
for example anti-stain products.
NOTE 1 Commercial samples of timber can contain more than one botanical species. Agreed wood species names
(e.g. from ATIBT) can be mentioned as well as one can make reference to specific codes used, e.g. according to
EN 13556.
NOTE 2 Guidance on sampling is given in Annex A. Similar sampling as for natural durability is feasible for
modified wood.
Details of any modification or treatment process should be recorded.
6.2 Wood quality
The following requirements are specific for wood to be tested in realtion to natural durability and as such
valid only for non-modified wood.
Record the physical characteristics of the timber sample, for example the sizes of logs/planks, the
presence of resin pockets, cross-grain, knots, sapwood and where possible record the widths of annual
rings and the proportion of latewood. For logs, record the position in the trunk if known.
The wood shall be free from cracks, stain, decay, insect damage or other defects. The wood shall not have
been water-stored, floated, chemically treated or steamed.
NOTE 1 Wood that has been kiln dried at temperatures below 60°C can be used.
NOTE 2 There are no special requirements for modified wood.
6.3 Provision of the test specimens
Reject at least the outer 10 mm from lateral faces of planks and 50 mm from the end grain; reject at least
50 mm from the end grain of logs.
Condition the wood to a mass fraction of (12 ± 2) % moisture content or conditioned at (65 ± 5) % RH
and (20 ± 2) °C for at least 2 weeks. Prepare planed strips having a cross-section of
(25 ± 0,5) mm x (15 ± 0,5) mm which avoid all obvious defects and which are entirely heartwood or
entirely sapwood. The longitudinal faces shall be parallel to the direction of the grain. The annual rings
shall not be parallel to the broad faces (contact angle to be greater than 5°) but otherwise may run in any
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direction. Transverse cuts shall be made neatly to give sharp edges and a fine-sawn finish to the end-
grain surfaces, to give timber test specimens (50 ± 0,5) mm long.
The test specimens shall originate from a minimum of three trees or shall be taken at random from a
stock originally of more than 500 test specimens and originating from at least five planks. Concerning
modified wood the test specimens should be taken from three batches or manufacturing lots.
6.4 Dimensions of test specimens
The dimensions of each timber test specimen measured at (12 ± 2) % moisture content or conditioned at
(65 ± 5) % RH (relative humidity) and (20 ± 2) °C for at least 2 weeks, shall be
(50 ± 0,5) mm x (25 ± 0,5) mm x (15 ± 0,5) mm.
NOTE 1 A two-prong electrical conductivity moisture meter is suitable for assessing moisture content.
3
NOTE 2 The nominal volume of each test specimen is 18,75 cm .
The dimensions of at least 10 specimens should be controlled randomly. If they are within the required
specifications, it is not necessary to measure the whole batch. If one of the controlled specimen does not
fulfil the requirement all specimens in the batch should be measured.
6.5 Number and distribution of test specimens
The timber test specimens are provided as:
— e Test specimens:
1
These are the test specimens of the test timber subjected to attack by the wood-destroying
basidiomycete fungi. Use at least 30 test specimens for exposure to each test fungus. Specimens
should be obtained from a minimum of five logs or five planks (mainly for testing natural durability
of a wood species) or if relevant from at least 3 batches or manufacturing lots (mainly relevant for
modified wood) and the sampling should take into account information provided in Annex A.
Mark each test specimen so that it can be identified throughout the test.
Materials under test that allow for ovendrying prior to testing do not require to include an additional
set of specimens related to moisture content. When assessing natural durability or modifed wood it
is necessary to avoid the impact of ovendrying at (103 ± 2) °C prior to testing and hence an additional
set of specimens is required: moisture content test specimens. For some modified material it can also
be necessary to avoid the impact of ovendrying.
— e Moisture content test specimens:
2
These are test specimens of the wood under test which are used to establish the moisture content of
the wood following conditioning to constant mass, to allow calculation of the initial dry mass of the
test specimens. Use at least 10 moisture content test specimens and a minimum of one from each log
or plank.
Mark each moisture content test specimen so that it can be identified throughout the test.
Since part of the mass loss might not be due to biological degradation it is recommended to include
also a set of specimens that is used as correction blocks for mass control the so-called check test
specimens for calculation of the correction value as provided for EN 113-1:2020, 7.5.
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The durability classes should be based on the degradation of the wood component of the material
under test. A correction might be needed to the masses considered e.g. when the wood material was
treated at high resin content.
7 Procedure
7.1 Preparation of the wood test specimens
7.1.1 Virulence control
Place the numbered reference wood test specimens in the oven (5.3.2) and leave them for 18 h to 24 h.
Cool to room temperature in a desiccator (5.3.3) and weigh to the nearest 0,01 g to determine the initial
dry mass (m ). Place the test specimens in the conditioning chamber (5.3.4) until they need to be
0
sterilized.
7.1.2 Wood unde
...
SLOVENSKI STANDARD
oSIST prEN 113-2:2018
01-december-2018
Trajnost lesa in lesnih proizvodov - Preskusna metoda proti glivam
odprtotrosnicam - 2. del: Ocenjevanje naravne ali izboljšane trajnosti
Durability of wood and wood-based products - Test method against wood destroying
basidiomycetes - Part 2: Assessment of inherent or enhanced durability
Dauerhaftigkeit von Holz und Holzprodukten - Prüfverfahren gegen Holz zerstörende
Basidiomyceten - Teil 2: Bewertung der natürlichen oder verbesserten Dauerhaftigkeit
Durabilité du bois et des matériaux dérivés du bois - Méthode d'essai vis-à-vis des
champignons basidiomycètes - Partie 2 : Détermination de la durabilité inhérente ou
améliorée
Ta slovenski standard je istoveten z: prEN 113-2
ICS:
71.100.50 .HPLNDOLMH]D]DãþLWROHVD Wood-protecting chemicals
oSIST prEN 113-2:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN 113-2:2018
DRAFT
EUROPEAN STANDARD
prEN 113-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2018
ICS 71.100.50
English Version
Durability of wood and wood-based products - Test
method against wood destroying basidiomycetes - Part 2:
Assessment of inherent or enhanced durability
Durabilité du bois et des matériaux dérivés du bois - Dauerhaftigkeit von Holz und Holzprodukten -
Méthode d'essai vis-à-vis des champignons Prüfverfahren gegen Holz zerstörende Basidiomyceten
basidiomycètes - Partie 2 : Détermination de la - Teil 2: Bewertung der natürlichen oder verbesserten
durabilité inhérente ou améliorée Dauerhaftigkeit
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 38.
If this draft becomes a European Standard, CEN 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 CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and 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 STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 113-2:2018 E
worldwide for CEN national Members.
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Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Principle . 6
5 Test material and apparatus . 7
5.1 Biological material . 7
5.1.1 Test fungi and virulence control timbers . 7
5.1.2 Virulence control timbers . 8
5.2 Products and reagents . 9
5.2.1 Culture medium . 9
5.3 Apparatus . 9
5.3.1 Culture vessels . 9
5.3.2 Drying oven . 9
5.3.3 Desiccators . 9
5.3.4 Conditioning chamber . 9
5.3.5 Culture chamber . 9
5.3.6 Test specimens supports . 9
5.3.7 Equipment for steam sterilization or access to a radiation source .10
5.3.8 Ordinary laboratory equipment .10
6 Test specimens .10
6.1 Species and source of wood .10
6.2 Wood quality .10
6.3 Provision of the test specimens .10
6.4 Dimensions of test specimens .11
6.5 Number and distribution of test specimens .11
7 Classification, designation and coding .11
7.1 Preparation of the timber test specimens.11
7.1.1 Virulence control timber .11
7.1.2 Test timber .12
7.2 Exposure to fungi .13
7.3 Culture conditions and duration of test .13
7.4 Assessment of test .13
7.4.1 Examination of the test specimens .13
7.4.2 Validity of results .13
7.4.3 Assessment of results .14
8 Statement of results .14
9 Test report .14
Annex A (informative) Guidance on sampling .16
A.1 Introduction .16
A.2 Sampling from logs .16
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A.3 Sampling from commercial supplies of sawn timber . 16
A.4 Sampling from modified timber . 17
Annex B (informative) Methods of sterilization . 18
B.1 Ionizing radiation . 18
B.2 Steam . 18
Annex C (informative) Test vessels . 19
Annex D (informative) Example of a test report. 26
Annex E (informative) Test fungi . 27
E.1 General information on maintaining and acquisition of test strains . 27
E.2 Maintenance and treatment of test fungi . 27
E.3 Information regarding obligatory test fungi . 28
E.4 Information regarding optional test fungi . 28
Annex F (informative) Assessment of results . 31
Bibliography . 33
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European foreword
This document (prEN 113-2:2018) has been prepared by Technical Committee CEN/TC 38 “Durability of
wood and wood-based products”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede CEN/TS 15083-1:2005
This document will supersede EN 113:1996 and EN 113:1996/A1:2004.
Compared to current EN 113, the following modifications are:
— a second part has been included;
— this second part corresponds to the CEN/TS 15083-1:2005 document;
— the two parts of the new EN 113 deal with similar testing but relate to a different scope.
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Introduction
This document specifies a laboratory method of test which gives a basis for the assessment of the
biological durability of a sample of wood or wood product against attack by wood-destroying
basidiomycetes. Specifically the natural durability of a wood species can vary depending on the
conditions of growth such as climate and soil type. For this reason, the durability established using the
method described in this document will relate only to the sample of timber tested. Guidance on sampling
is given in Annex A.
This laboratory method provides one criterion by which the durability of the timber can be assessed. It
is recommended that this information is supplemented by data from other relevant tests, and above all
by practical experience.
The procedures described in this standard method are intended to be carried out by suitably trained
and/or supervised specialists.
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1 Scope
This document specifies a method of test for determining the natural durability of a timber against wood-
destroying basidiomycetes cultured on a malt extract agar medium. The method is applicable to all timber
species.
Furthermore this method can be used to test modified or treated wood. The test method described in this
part 2 of EN 113 can be applied to specific wood species, commercial supplies of sawn timber, wood-
based materials, wood treated with preservatives and modified wood including heat-treated wood.
However, this standard is not intended to determine the effectiveness of wood preservatives used to
prevent decay.
NOTE 1 Determining the efficacy of wood preservatives used to prevent decay is the scope of EN 113-1.
NOTE 2 This method can be used in conjunction with an ageing procedure, for example EN 73 or EN 84.
Annex A (informative) contains a guidance on sampling.
Annex B (informative) contains some methods of sterilization.
Annex C (informative) contains information on the test vessels.
Annex D (informative) contains an example of a test report.
Annex E (informative) contains information on the test fungi.
Annex F (informative) contains the assessment of the results.
2 Normative references
There are no normative references in this document.
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
supplier
sponsor of the test (person or company providing the sample of timber to be tested)
4 Principle
Test specimens of the timber under test and reference timber test specimens are exposed to attack by
pure cultures of basidiomycetes. After a prescribed period of incubation under defined conditions, the
percentage loss in dry mass of the test specimens is used to establish the timber durability classification
of the timber under test.
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5 Test material and apparatus
5.1 Biological material
5.1.1 Test fungi and virulence control timbers
5.1.1.1 General
The test fungi to be used are as follows and relate to corresponding virulence control timbers.
It is required that the virulence control timbers used shall show a mass loss of at least 30 % with one of
the test fungi.
5.1.1.2 Hardwoods: beech as virulence control timber
Obligatory fungi:
— Coniophora puteana (Schumacher ex Fries) Karsten (BAM Ebw. 15):
Loss in mass of beech in 16 weeks: minimum 20 %.
— Trametes versicolor (L.) Lloyd (CTB 863A):
Loss in mass of beech in 16 weeks: minimum 20 %.
5.1.1.3 Softwoods: Scots pine sapwood as virulence control timber
Obligatory fungi:
— Coniophora puteana (Schumacher ex Fries) Karsten (BAM Ebw. 15):
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
— Rhodonia placenta (Fr.) Niemelä, K.H. Larss. and Schigel (FPRL 280):
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
5.1.1.4 Modified wood: both beech and Scots pine sapwood as virulence control timber
Obligatory fungi:
— Coniophora puteana (Schumacher ex Fries) Karsten (BAM Ebw. 15) for both softwoods and
hardwoods:
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
Loss in mass of beech in 16 weeks: minimum 20 %.
— Rhodonia placenta (Fr.) Niemelä, K.H. Larss. and Schigel (FPRL 280) for softwoods:
Loss in mass of Scots pine sapwood in 16 weeks: minimum 20 %.
— Trametes versicolor (L.) Lloyd (CTB 863A) for hardwoods:
Loss in mass of beech in 16 weeks: minimum 20 %.
5.1.1.5 Maintenance of strains
The strains shall be maintained and treated so that its virulence is conserved and ensured (see Annex E).
The strains shall be maintained and treated (frequency of subculturing, alternation of culture media, etc.)
in accordance with the instructions of their laboratory of origin (see E.2).
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NOTE The parent strain is maintained in the laboratory of its origin so as to conserve and to ensure its vigour.
If tests are not undertaken regularly or if a strain shows signs of degeneration a new standard culture of
the strain should be obtained from the laboratory of its origin for each test (see E.2).
When new strains are received, the virulence shall be tested to ensure the strain can achieve the
minimum loss in mass (see 5.1.1.2 and 5.1.1.3).
5.1.2 Virulence control timbers
5.1.2.1 Species used for the tests
— scots pine sapwood (Pinus sylvestris Linnaeus) for tests with softwoods;
— beech (Fagus sylvatica Linnaeus) for tests with hardwoods;
— for modified wood both Scots pine sapwood and beech should be used.
5.1.2.2 Wood quality
The wood shall be free from cracks, stain, decay, insect damage or other defects. The wood shall not have
been water-stored, floated, chemically treated or steamed.
NOTE Wood that has been kiln dried at temperatures not above 60 °C can be used.
The Scots pine shall be exclusively sapwood containing little resin and having between 2,5 and 8 annual
growth rings per 10 mm. The proportion of latewood in the annual rings shall not exceed 30 % of the
whole.
The beech shall be even-grained, free from tyloses, discolouration and red heart. It shall have between 2
and 6 annual growth rings per 10 mm.
5.1.2.3 Provision of virulence control specimens
Prepare planed strips having a cross-section of (25 ± 0,5) mm x (15 ± 0,5) mm. The longitudinal faces
shall be parallel to the direction of the grain. The annual rings shall not be parallel to the broad faces
(contact angle to be greater than 5) but otherwise may run in any direction. Make transverse cuts, neatly
to give sharp edges and a fine-sawn finish to the end-grain surfaces, to give virulence control specimens
(50 ± 0,5) mm long.
The virulence control specimens shall originate from a minimum of three trees or shall be taken at
random from a stock originally of more than 500 test specimens and originating from at least five planks.
5.1.2.4 Dimensions and density of virulence control specimens
The dimensions of each reference timber virulence control specimen at (12 ± 2) % moisture content or
conditioned at 65 ± 5 % RH and 20 ± 2 °C for at least 2 weeks, shall be (50 ± 0,5) mm
x (25 ± 0,5) mm x (15 ± 0,5) mm.
NOTE A two-prong electrical conductivity moisture meter is suitable for assessing moisture content.
In a batch of virulence control specimens, the density of an individual is permitted to differ from the mean
value of the batch by ± 10 %.
5.1.2.5 Number and distribution of virulence control specimens
Use at least 10 reference timber virulence control specimens for each test fungus. Mark each viruelence
control specimen so that it can be identified throughout the test.
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5.2 Products and reagents
5.2.1 Culture medium
The culture medium shall be a malt agar medium with the following composition:
— malt extract:
— in concentrated form: (50 ± 0,5) g;
— in powder form: (40 ± 0,5) g.
— agar causing no inhibition of growth of fungi: (20 ± 0,5) g to (30 ± 0,5) g;
— de-ionized water; quantity to make up to 1000 g.
NOTE Preferably use water conforming to grade 3 of ISO 3696.
Prepare this medium by warming the mixture in a boiling water bath or steam bath, stirring until
completely dissolved.
Place in each culture vessel (5.3.1) a sufficient quantity of the medium to provide a minimum depth of
3 mm to 4 mm when in its in-use position. Close the vessels as specified in 5.3.1 and sterilize in an
autoclave at 121 °C for 20 min. Let the vessels cool in their in-use position.
5.3 Apparatus
5.3.1 Culture vessels
Kolle flasks or equivalent vessels with a capacity of between 400 ml and 650 ml providing a flat surface
2 2
area of between 85 cm and 120 cm for the medium and allowing air exchange.
NOTE 1 Examples of suitable vessels are given in Annex C.
NOTE 2 Kolle flasks are usually plugged with a wad of cotton wool. Other culture vessels are usually fitted with
leakproof lids, the centres of which are pierced with a round hole of up to 15 mm diameter and plugged with a wad
of cotton wool.
5.3.2 Drying oven
Capable of being controlled at (103 ± 2) °C.
5.3.3 Desiccators
With efficient desiccant (silica gel for example).
5.3.4 Conditioning chamber
Well ventilated and controlled at (20 ± 2) °C and (65 ± 5) % relative humidity.
5.3.5 Culture chamber
Incubator or room, dark and controlled at (22 ± 2) °C and (70 ± 5) % relative humidity.
5.3.6 Test specimens supports
Made of glass, stainless steel or any other inert material, that is to say, with no risk of having any effect
on the culture medium, the fungus, the wood, or of modifying itself. The supports are used to prevent
direct contact of the specimens with the culture medium, but shall not separate them from it by more
than 3 mm.
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If abnormally high moisture contents are experienced consistently, use of specimen supports of
approximately 5 mm thick may help to control the problem. If thicker specimen supports are used, this
should be recorded in the test report.
NOTE Supports can be capable of holding either one or two test specimens.
5.3.7 Equipment for steam sterilization or access to a radiation source
See Annex B.
5.3.8 Ordinary laboratory equipment
Including a balance capable of weighing to an accuracy of 0,01 g.
6 Test specimens
6.1 Species and source of wood
Ensure that the species of each plank or log to be tested has been identified correctly and record both the
botanical and the trade name. Obtain as much information as possible on the origin and history of the
sample (see Annex A). The sample of timber shall be free from penetrating wood preservative treatments,
for example anti-stain products.
NOTE 1 Commercial samples of timber can contain more than one botanical species.
NOTE 2 Guidance on sampling is given in Annex A.
6.2 Wood quality
Record the physical characteristics of the timber sample, for example the sizes of logs/planks, the
presence of resin pockets, cross-grain, knots, sapwood and where possible record the widths of annual
rings and the proportion of latewood. For logs, record the position in the trunk if known.
The wood shall be free from cracks, stain, decay, insect damage or other defects. The wood shall not have
been water-stored, floated, chemically treated or steamed.
NOTE Wood that has been kiln dried at temperatures below 60°C can be used.
6.3 Provision of the test specimens
Reject at least the outer 10 mm from lateral faces of planks and 50 mm from the end grain; reject at least
50 mm from the end grain of logs.
Condition the wood to (12 ± 2) % (m/m) moisture content or conditioned at 65 ± 5 % RH and 20 ± 2 °C
for at least 2 weeks. Prepare planed strips having a cross-section of (25 ± 0,5) mm x (15 ± 0,5) mm which
avoid all obvious defects and which are entirely heartwood or entirely sapwood. The longitudinal faces
shall be parallel to the direction of the grain. The annual rings shall not be parallel to the broad faces
(contact angle to be greater than 5°) but otherwise may run in any direction. Transverse cuts shall be
made neatly to give sharp edges and a fine-sawn finish to the end-grain surfaces, to give timber test
specimens (50 ± 0,5) mm long.
The test specimens shall originate from a minimum of three trees or shall be taken at random from a
stock originally of more than 500 test specimens and originating from at least five planks. Concerning
modified wood the test specimens should be taken from three batches or manufacturing lots.
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6.4 Dimensions of test specimens
The dimensions of each timber test specimen measured at 12 ± 2 % moisture content or conditioned at
65 ± 5 % RH and 20 ± 2 °C for at least 2 weeks, shall be (50 ± 0,5) mm x (25 ± 0,5) mm x (15 ± 0,5) mm.
NOTE 1 A two-prong electrical conductivity moisture meter is suitable for assessing moisture content.
NOTE 2 The nominal volume of each test specimen is 18,75 cm3.
6.5 Number and distribution of test specimens
The timber test specimens are provided as:
— e Test specimens:
1
— these are the test specimens of the test timber subjected to attack by the wood-destroying
basidiomycete fungi. Use at least 30 test specimens for exposure to each test fungus. Specific for
testing natural durability of a wood species, specimens should be obtained from a minimum of
five logs or five planks or if relevant from at least 3 batches and the sampling should take into
account information provided in Annex A.;
— mark each test specimen so that it can be identified throughout the test.
Materials under test allowing to ovendry prior to testing e.g. do not require to include an additional set
of specimens related to moisture content. When assessing natural durability or preservative treated
wood it is necessary to avoid the impact of ovendrying at 103 ± 2 °C prior to testing and hence an
additional set of specimens is required:
— e Moisture content test specimens:
2
— these are test specimens of the test timber which are used to establish the moisture content of
the timber following conditioning to constant mass, to allow calculation of the initial dry mass of
the test specimens. Use at least 10 moisture content test specimens and a minimum of one from
each log or plank.
Since part of the mass loss might not be due to biological degradation it is recommended to include also
a set of specimens that is used as correction blocks for mass control as is also provided for EN113 part 1.
The durability classes should be based on the degradation of the wood component of the material under
test. A correction might be needed to the masses considered when non-wood material is present like in
wood polymer composites (WPC).
7 Classification, designation and coding
7.1 Preparation of the timber test specimens
7.1.1 Virulence control timber
Place the numbered reference timber test specimens in the oven (5.3.2) and leave them there for 18 h to
24 h. Cool to room temperature in a desiccator (5.3.3) and weigh to the nearest 0,01 g to determine the
initial dry mass (m ). Place the test specimens in the conditioning chamber (5.3.4) until they need to be
0
sterilized.
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7.1.2 Test timber
If the test specimens are to be subjected to an ageing procedure, the procedure should be carried out
prior to conditioning to constant mass to avoid the need to establish changes in mass due to the ageing
procedure.
Place the numbered timber test specimens (e ) and the moisture content test specimens (e ) in the
1 2
conditioning chamber (5.3.4) until weighings of sample test specimens at 24 h intervals are
within ± 0,01 g. Weigh the timber test specimens and the moisture content test specimens and record the
initial conditioned mass (m ).
1
Calculate the mean density of the timber test specimens using the mean conditioned mass and the
nominal volume (see 6.4).
— option A: for test materials that cannot be ovendried prior to fungal test (e.g. untreated timber,
modified wood that can be altered by the drying):
— place the moisture content test specimens in the oven (5.3.2) and leave them there for 18 h to
24 h. Cool to room temperature in a desiccator (5.3.3) and weigh to the nearest 0,01 g to
determine the oven dry mass (m );
0
— calculate the moisture content of each moisture content test specimen by expressing the mass of
water (m - m ) as a percentage of the oven dry mass (m );
1 0 0
— calcul
...
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