prEN 20-1

Wood preservatives - Determination of the protective effectiveness against Lyctus Brunneus (Stephens) - Part 1: Application by surface treatment (laboratory method)

This part of the EN 20 series specifies a method for the determination of the protective effectiveness or the toxic values of a wood preservative against infection by Lyctus brunneus (Stephens) when the product is applied as a surface treatment to wood.
This method is applicable to:
- water-insoluble chemicals which are being studied as active insecticides; or
- organic formulsation, as supplied or as prepared in the laboratory by dilution of concentrates; or
- organic water-dispersible formulations as supplied or as prepared in the laboratory by dilution of concentrates; or
- water-soluble materials, for example salts.
NOTE This method can be used in conjuction with ageing procedures, which do not remove the added nutrient.

Holzschutzmittel - Bestimmung der vorbeugenden Wirkung gegenüber Lyctus Brunneus (Stephens) - Teil 1: Oberflächenbehandlung (Laboratoriumsverfahren)

Dieser Teil der Normenreihe EN 20 legt ein Verfahren zur Bestimmung der vorbeugenden Wirkung oder der Grenze der Wirksamkeit eines Holzschutzmittels gegen Befall durch Lyctus brunneus (Stephens) fest, bei dem das Schutzmittel durch Behandlung seiner Oberfläche auf das Holz aufgebracht wird.
Das Verfahren ist anzuwenden für:
- nicht wasserlösliche chemische Erzeugnisse, die als insektizide Wirkstoffe untersucht werden; oder
- organische Formulierungen im Anlieferungszustand oder in der Form, wie sie im Labor aus Konzentraten hergestellt werden; oder
- in Wasser dispergierbare organische Formulierungen im Anlieferungszustand oder in der Form, wie sie im Labor aus Konzentraten hergestellt werden; oder
- wasserlösliche Erzeugnisse, z. B. Salze.
ANMERKUNG Das Verfahren kann in Verbindung mit Alterungsverfahren angewendet werden, die die zugegebene Nährlösung nicht entfernen.

Produits de préservation du bois - Détermination de l'efficacité protectrice vis-à-vis de Lyctus Brunneus (Stephens) - Partie 1 : Application par traitement de surface (Méthode de laboratoire)

La présente partie de la série de normes EN 20 spécifie une méthode de détermination de l'efficacité protectrice ou du seuil d'efficacité d'un produit de préservation du bois contre l'infestation par le Lyctus brunneus (Stephens) lorsque ce produit est appliqué au bois en tant que traitement de surface.
La présente méthode est applicable :
- aux produits chimiques non hydrosolubles étudiés en tant que matières actives insecticides ; ou
- aux formules organiques telles qu'elles sont livrées ou obtenues en laboratoire par dilution de concentrés ; ou
- aux formules organiques hydrodispersables telles qu'elles sont livrées ou obtenues en laboratoire par dilution de concentrés ; ou
- aux produits hydrosolubles tels que les sels.
NOTE La présente méthode peut être utilisée conjointement avec des épreuves de vieillissement qui n'éliminent pas la solution nutritive ajoutée.

Zaščitna sredstva za les - Določanje učinkovitosti preventivne zaščite proti rjavemu parketarju Lyctus brunneus (Stephens) - 1. del: Površinsko nanašanje (laboratorijska metoda)

General Information

• Status: Not Published
• Publication Date: 14-Aug-2024
• ICS: 71.100.50 - Wood-protecting chemicals
• Technical Committee: CEN/TC 38 - Durability of wood and derived materials
• Drafting Committee: CEN/TC 38/WG 24 - Insect testing - (beetles - termites)
• Current Stage: 4060 - Closure of enquiry - Enquiry
• Start Date: 29-Dec-2022
• Due Date: 22-Dec-2022
• Completion Date: 29-Dec-2022
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Ref Project: oSIST prEN 20-1:2022 - Wood preservatives - Determination of the protective effectiveness against Lyctus Brunneus (Stephens) - Part 1: Application by surface treatment (laboratory method)

Relations

• Revises: EN 20-1:1992 - Wood preservatives - Determination of the protective effectiveness against Lyctus Brunneus (Stephens) - Part 1: Application by surface treatment (laboratory method)
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 20-1:2022
01-december-2022
Zaščitna sredstva za les - Določanje učinkovitosti preventivne zaščite proti
rjavemu parketarju Lyctus brunneus (Stephens) - 1. del: Površinsko nanašanje
(laboratorijska metoda)

Wood preservatives - Determination of the protective effectiveness against Lyctus

Brunneus (Stephens) - Part 1: Application by surface treatment (laboratory method)

Holzschutzmittel - Bestimmung der vorbeugenden Wirkung gegenüber Lyctus Brunneus
(Stephens) - Teil 1: Oberflächenbehandlung (Laboratoriumsverfahren)

Produits de préservation du bois - Détermination de l'efficacité protectrice vis-à-vis de

Lyctus Brunneus (Stephens) - Partie 1 : Application par traitement de surface (Méthode

de laboratoire)
Ta slovenski standard je istoveten z: prEN 20-1
ICS:
71.100.50 Kemikalije za zaščito lesa Wood-protecting chemicals
oSIST prEN 20-1:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 20-1:2022
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oSIST prEN 20-1:2022
DRAFT
EUROPEAN STANDARD
prEN 20-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2022
ICS 71.100.50 Will supersede EN 20-1:1992
English Version
Wood preservatives - Determination of the protective
effectiveness against Lyctus Brunneus (Stephens) - Part 1:
Application by surface treatment (laboratory method)

Produits de préservation du bois - Détermination de Holzschutzmittel - Bestimmung der vorbeugenden

l'efficacité protectrice vis-à-vis de Lyctus Brunneus Wirkung gegenüber Lyctus Brunneus (Stephens) - Teil

(Stephens) - Partie 1: Application par traitement de 1: Oberflächenbehandlung (Laboratoriumsverfahren)

surface (Méthode de laboratoire)

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, 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, Türkiye 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

© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 20-1:2022 E

worldwide for CEN national Members.
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prEN 20-1:2022 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 Principle ............................................................................................................................................................. 5

5 Test materials and apparatus ..................................................................................................................... 6

5.1 Biological material .......................................................................................................................................... 6

5.2 Products and reagents ................................................................................................................................... 6

5.3 Apparatus ........................................................................................................................................................... 6

6 Sampling ............................................................................................................................................................. 7

7 Test specimens ................................................................................................................................................. 7

7.1 Species of wood ................................................................................................................................................ 7

7.2 Quality of wood ................................................................................................................................................ 8

7.3 Provision of the test specimens ................................................................................................................. 8

7.4 Dimensions of test specimens .................................................................................................................... 8

7.5 Number of test specimens ............................................................................................................................ 8

8 Procedure........................................................................................................................................................... 9

8.1 Prior impregnation of the test specimens with a nutrient solution ............................................. 9

8.1.1 Composition of the nutrient solution ....................................................................................................... 9

8.1.2 Method of impregnation of nutrient solution ....................................................................................... 9

8.1.3 Drying of test specimens .............................................................................................................................. 9

8.2 Conditioning of specimens before end sealing ..................................................................................... 9

8.3 Preparation of test specimens .................................................................................................................... 9

8.3.1 Sealing of transverse surfaces .................................................................................................................... 9

8.3.2 Treatment of test specimens ....................................................................................................................... 9

8.4 Drying and conditioning of the test specimens after treatment ................................................. 10

8.5 Exposure of the test specimens to the insects ................................................................................... 11

8.6 Conditions and duration of test .............................................................................................................. 11

8.7 Examination of the test specimens ........................................................................................................ 11

9 Validity of test ................................................................................................................................................ 11

10 Expression of results ................................................................................................................................... 12

10.1 Assessment of the protective effectiveness ........................................................................................ 12

10.2 Toxic values .................................................................................................................................................... 12

11 Test report ...................................................................................................................................................... 12

Annex A (informative) Example of a test report ............................................................................................ 14

Annex B (informative) Technique for culturing Lyctus brunneus .......................................................... 16

Annex C (informative) Principal parasites and predators of Lyctus ...................................................... 20

Bibliography ................................................................................................................................................................. 21

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oSIST prEN 20-1:2022
prEN 20-1:2022 (E)
European foreword

This document (prEN 20-1:2022) 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 EN 20-1:1992.

Significant technical differences between this document and EN 20-1:1992 are as follows:

a) the source of peptone is no longer specified (5.2.6);

b) other wood species than oak may be used for the test under certain circumstances (7.1);

c) tests with solvent control may be omitted, when the solvent is water (7.5);
d) new pictures were used for Figure B.1, Figure B.2, and Figure B.3.

NOTE Test results obtained according to earlier versions of this document and when the tests had started

before this version of EN 20-1 was published are considered valid.
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Introduction

This Part of the EN 20 series describes a laboratory method of test which gives a basis for assessment of

the protective effectiveness of a wood preservative, when applied as a surface treatment, against Lyctus

brunneus. It allows the deternination of the concentration at which the product prevents the development

of infestation from egg-laying.
It can also be used with formulations ready for use.

The species Lyctus brunneus is chosen because of its particular practical relevance and because it can be

used easily in laboratory tests. The method can be used with other lyctid species, but the results might

not be comparable with those obtained with Lyctus brunneus.

The test specimens are enriched with a defined nutrient solution, before exposure to egg-laying, in order

to ensure uniformity of nutrient quality of test specimens between different laboratories.

This laboratory method provides one criterion by which the value of a product can be assessed. In making

this assessment, the methods by which the preservative may be applied should be taken into account. It

is further recommended that results from this test should be supplemented by those from other

appropriates tests, and above all by comparison with practical experience.

When products which are very active at low concentrations are used, it is very important to take suitable

precautions to isolate and separate, as far as possible, operations involving chemical products, other

products, treated wood, laboratory apparatus and clothing. Suitable precautions should include the use

of separate rooms, areas within rooms, extraction facilities and conditioning chambers as well as special

training for personnel.
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1 Scope

This part of the EN 20 series specifies a method for the determination of the protective effectiveness or

the toxic values of a wood preservative against infection by Lyctus brunneus (Stephens) when the product

is applied as a surface treatment to wood.
This method is applicable to:
— water-insoluble chemicals which are being studied as active insecticides; or

— organic formulsation, as supplied or as prepared in the laboratory by dilution of concentrates; or

— organic water-dispersible formulations as supplied or as prepared in the laboratory by dilution of

concentrates; or
— water-soluble materials, for example salts.

NOTE This method can be used in conjuction with ageing procedures, which do not remove the added nutrient.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 835-1:1981, Laboratory glassware — Graduated pipettes — Part 1: General requirements

ISO 3696:1987, Water for analytical laboratory use — Specification and test methods

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 https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
representative sample

sample having its physical or chemical characteristics identical to the volumetric average characteristics

of the total volume being sampled
3.2
supplier
sponsor of the test
4 Principle
Depending on the test being carried out either:

— a set of test specimens of a susceptible wood species is impregnated with nutrient solution and then

surface treated with a solution of the preservative; or

— if toxic values are to be determined, several sets of tests specimens of a susceptible wood species are

impregnated with a nutrient solution and then surface treated with a series of solutions in which the

concentration of preservative is ranged in a given progression.
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The treated test specimens are exposed to adult Lyctus brunneus and the resulting attack compared to

that in untreated controls. If the preservation has been prepared in the laboratory by dilution of a

concentrate or by dissolution of a solid, the resulting attack is also compared to that in solvent or diluent

treated controls.
5 Test materials and apparatus
5.1 Biological material

Lyctus brunneus (Stephens), insects emerged from cultures not more than 48h before use in the test.

NOTE The culturing of Lyctus brunneus requires care in order to obtain a regular supply of adults which have

not already laid eggs. The culturing technique, which experiences has shown to be suitable, is described in Annex B.

5.2 Products and reagents

5.2.1 Paraffin wax, for sealing the relevant surfaces of test specimens to be treated with solutions in

which water is the continuous phase

NOTE Paraffiin wax with a setting point of 52 °C to 54 °C has been found to be suitable.

5.2.2 Gelatin, for sealing the relevant surfaces of specimens to be treated with solutions in which an

organic solvent is the continuous phase

5.2.3 Paste, for securing filter paper. The paste shall be starch-free, non-toxic to Lyctus and insoluble

in the product under test
NOTE Sodium carboxymethyl cellulose, food grade, has been found to be suitable.
5.2.4 Water, complying with grade 3 of ISO 3696

5.2.5 Solvent or diluent, a volatile liquid that will dissolve or dilute the preservative but does not leave

a residue in the wood at the end of the post-treatment conditioning period that has a toxic effet on the

insects
CAUTION — Do not use benzene or other solvents which pose on health risk.
5.2.6 Peptone
5.2.7 D (+)-glucose
5.2.8 Filter paper ordinary quality, medium-fast grade
5.2.9 Fine cloth of cotton of linen, with a mesh aperture of less than 0,3 mm
5.3 Apparatus

5.3.1 Culturing chamber, with air circulation, controlled at (26 ± 2) °C, and at relative humidity

(75 ± 5) %

5.3.2 Conditioning chamber, well ventilated, controlled at (20 ± 2) °C and relative humidity

(65 ± 5) %

The conditioning of specimens may be carried out in the laboratory work area (see 5.3.4) provided that

this has the conditions specified for the conditioning chamber (see 5.3.2).
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5.3.3 Drying chamber, well ventilated, controlled at (30 ± 2) °C

5.3.4 Laboratory work area, well ventilated, where treatment of the test specimens is carried out

CAUTION — It is essential to follow safety procedures for handling flammable and toxic materials. Avoid

excessive exposure of operators to solvents of their vapours.

5.3.5 Testing chamber, with conditions identical to those of the culturing chamber (see 5.3.1)

5.3.6 Vacuum vessel(s), fitted with stopcocks

5.3.7 Vaccum pump, fitted with a pressure gauge and capable of maintaining a pressure of 700 Pa

5.3.8 Weights, to provide ballast for the test specimens. The weights shall not react with any materials

with which they come into contact during the test
5.3.9 Pipette, of the specified in ISO 835-1

5.3.10 Safety equipment and protective clothing, appropriate for the test product and the test solvent,

to ensure the safety of the operator

5.3.11 Test container, suitable for holding the test specimens and of material resistant to the solvents

used

NOTE Jars of approximately 60 mm diameter and 100 mm height have been found to be suitable.

5.3.12 Ordinary laboratory equipment, including a balance capable of weighing to an accuracy of

0,01 g

5.3.13 X-ray apparatus, (optional) with tungsten target and beryllium window, with voltage and

current continuously variable in the range:
— voltage: 10 kV to 50 kV;
— current: 0 mA to 15 mA
6 Sampling

The sample of preservative shall be representative of the product to be tested. Samples shall be stored

and handled in accordance with any written recommendations from the supplier.

For the sampling of preservatives from bulk supplies, the procedure given in EN 212 should be used.

7 Test specimens
7.1 Species of wood

The test shall be carried out on European oak. This shall comprise sessile oak, Quercus petraea

(Mattuschka) Lieblin, and pedunculate oak, Quercus robur Linnaeus.
100 Pa = 1 mbar.
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Other wood species, with demonstrated susceptiblity to Lyctus brunneus (Stephens), like Triplochiton

scleroxylon, may be used instead of European oak.
7.2 Quality of wood

Use only sound sapwood with between 2 annual growth rings per 10 mm and 10 annual growth rings per

10 mm, straight-grainded without knots. The wood, having few tyloses, shall not have been floated or

subjected to any chemical treatment and shall be dried without delay as described in 7.3.

7.3 Provision of the test specimens

Remove the bark from the freshly cut billets and then cut them into lengths (from which strips 25 mm ×

15 mm in cross-section will be cut). Immediately place the billets in the drying chamber (5.3.3) stacked

with spaces between individual billets so as to allow movement of air through the stack. Retain the billets

in the drying chamber until their moisture contents are reduced to 15 % (m/m) .

NOTE Moisture meters of the two-pronged electrical conductivity type are suitable for assessing moisture

content.

Cut the sapwood of the dried billets into planted strips 25 mm × 15 cross section and with the wide

longitudinal faces oriented tangentially. Cut the specimens for test from the planed strips. The individual

specimens for test shall be cut cleanly and shall have sharp edges.

The specimens required for a test shall be taken from at least tow lots each corresponding to a different

tree or two sapwood strips taken diametrically opposed positions in the same log. The specimens from

the two sources shalle be combined and the test specimens taken at random from them.

7.4 Dimensions of test specimens

The dimensions of each specimen after one week in the conditioning chamber (5.3.2) shall be:

— (50 ± 0,5) mm × (25 ± 0,5) mm × (15 ± 0,5) mm
NOTE The total surface area of the longitudinal faces is theoretically 40 cm .
Mark each specimen so that it can be identified throught the test.
7.5 Number of test specimens
Use:
a) for each preservative and each concentration: five specimens (see 7.4);

b) for a complete test of any given preservative: five untreated control specimens (see 7.4);

c) if a solvent or diluent (water included) is used: five control specimens (7.4) treated with that solvent

or diluent (5.2.4 or 5.2.5).

Control test specimens under c) may be omitted if the solvent or diluent is water accoding to 5.2.4.

As determined in accordance to ISO 3130.
...