oSIST prEN 117:2022

Wood preservatives - Determination of toxic values against Reticulitermes species (European termites) (Laboratory method)

This document specifies a method for the determination of the toxic values of a wood preservative against the Reticulitermes species of European termites ). This method is applicable to: - water-insoluble chemicals which are being studied as active insecticides; - organic water-dispersible formulations as supplied or as prepared in the laboratory by dilution of concentrates; and - water soluble materials, for example salts. NOTE This method can be used in conjunction with an ageing procedure, for example EN 73.

Holzschutzmittel - Bestimmung der Grenze der Wirksamkeit gegenüber Reticulitermes-Arten (Europäische Termiten) (Laboratoriumsverfahren)

Dieses Dokument legt ein Verfahren zur Bestimmung der Grenze der Wirksamkeit eines Holzschutzmittels gegenüber Reticulitermes-Arten von europäischen Termiten  fest.
Das Verfahren ist anzuwenden für:
- nicht wasserlösliche chemische Erzeugnisse, die als insektizide Wirkstoffe untersucht werden;
- organische, in Wasser dispergierbare Formulierungen im Anlieferungszustand oder in der Form, wie sie im Labor durch Verdünnung aus Konzentraten hergestellt werden; und
- wasserlösliche Stoffe, zum Beispiel Salze.
ANMERKUNG Das Verfahren kann in Verbindung mit Alterungsverfahren, zum Beispiel nach EN 73 oder EN 84, angewendet werden.

Produit de préservation du bois - Détermination du seuil d'efficacité contre les termites européens du genre Reticulitermes (Méthode de laboratoire)

Le présent document décrit une méthode de détermination du seuil d'efficacité d'un produit de préservation du bois contre les espèces de termites européens du genre Reticulitermes  .
Cette méthode s'applique :
- aux produits chimiques non hydrosolubles étudiés en tant que matières actives ;
- aux formulations organiques hydrodispersables telles qu'elles sont fournies ou préparées au laboratoire par dilution de concentrés ; et
- aux produits hydrosolubles, par exemple des sels.
NOTE Cette méthode peut être utilisée conjointement avec une épreuve de vieillissement, par exemple selon l'EN 73 ou l'EN 84.

Zaščitna sredstva za les - Ugotavljanje toksičnih vrednosti proti Reticulitermes santonensis (evropskim termitom) (laboratorijska metoda)

General Information

• Status: Not Published
• Public Enquiry End Date: 20-Dec-2022
• ICS: 71.100.50 - Wood-protecting chemicals
• Technical Committee: LLZ - Les, lesni izdelki in zaščita lesa
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 12-Oct-2022
• Due Date: 01-Mar-2023
• Completion Date: 21-Dec-2022
• Ref Project: prEN 117 - Wood preservatives - Determination of toxic values against Reticulitermes species (European termites) (Laboratory method)

Relations

• Revised: SIST EN 117:2013 - Wood preservatives - Determination of toxic values against Reticulitermes species (European termites) (Laboratory method)
• Effective Date: 28-Nov-2018
• Revised: SIST EN 117:2013 - Wood preservatives - Determination of toxic values against Reticulitermes species (European termites) (Laboratory method)
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 117:2022
01-december-2022
Zaščitna sredstva za les - Ugotavljanje toksičnih vrednosti proti Reticulitermes
santonensis (evropskim termitom) (laboratorijska metoda)

Wood preservatives - Determination of toxic values against Reticulitermes species

(European termites) (Laboratory method)

Holzschutzmittel - Bestimmung der Grenze der Wirksamkeit gegenüber Reticulitermes-

Arten (Europäische Termiten) (Laboratoriumsverfahren)

Produit de préservation du bois - Détermination du seuil d'efficacité contre les termites

européens du genre Reticulitermes (Méthode de laboratoire)
Ta slovenski standard je istoveten z: prEN 117
ICS:
71.100.50 Kemikalije za zaščito lesa Wood-protecting chemicals
oSIST prEN 117:2022 en,fr,de

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

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oSIST prEN 117:2022
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oSIST prEN 117:2022
DRAFT
EUROPEAN STANDARD
prEN 117
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2022
ICS 71.100.50 Will supersede EN 117:2012
English Version
Wood preservatives - Determination of toxic values
against Reticulitermes species (European termites)
(Laboratory method)

Produit de préservation du bois - Détermination du Holzschutzmittel - Bestimmung der Grenze der

seuil d'efficacité contre les termites européens du Wirksamkeit gegenüber Reticulitermes-Arten

genre Reticulitermes (Méthode de laboratoire) (Europäische Termiten) (Laboratoriumsverfahren)

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 117:2022 E

worldwide for CEN national Members.
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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 ................................................................................................................................................... 6

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

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

5.3 Apparatus ........................................................................................................................................................... 7

6 Sampling ............................................................................................................................................................. 8

7 Test specimens ................................................................................................................................................. 8

7.1 Species of wood ................................................................................................................................................ 8

7.2 Wood quality ..................................................................................................................................................... 8

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

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

7.5 Number and distribution of test specimens .......................................................................................... 9

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

8.1 Preparation of test specimens .................................................................................................................... 9

8.1.1 Conditioning of test specimens prior to treatment ............................................................................ 9

8.1.2 Treatment of test specimens ....................................................................................................................... 9

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

8.2 Exposure of the test specimens to the insects ................................................................................... 10

8.2.1 Collecting and selecting the termites .................................................................................................... 10

8.2.2 Instalaltion of the termites ....................................................................................................................... 11

8.2.3 Exposure .......................................................................................................................................................... 12

8.3 Conditions and duration of test .............................................................................................................. 13

8.3.1 Exposure .......................................................................................................................................................... 13

8.3.2 Maintaining of moisture content ............................................................................................................ 13

8.4 Examination of the test specimens and colonies .............................................................................. 14

8.4.1 Assessments ................................................................................................................................................... 14

9 Expression of results ................................................................................................................................... 15

10 Test report ...................................................................................................................................................... 15

Annex A (informative) Example of a test report ............................................................................................ 17

Annex B (informative) Example of a method of culturing termites ........................................................ 19

Annex C (informative) Environmental, health and safety precautions within

chemical/biological laboratory .............................................................................................................. 20

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

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European foreword

This document (prEN 117:2022) 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 117:2012.

Significant technical differences between this document and EN 117:2012 are as follows:

a) the required purity of fine white quartz sand was lowered (5.2.1.1);

b) the values for the examination of termite attack in rating 2i) and 3i) were slightly changed to close

rating gaps (8.4.1.2).

NOTE 1 The species name “Reticulitermes santonensis” is officially withdrawn and replaced by Reticulitermes

flavipes. This document follows the new regulation.

NOTE 2 Test results obtained according to earlier versions of this document and when the tests had started

before this version of EN 117 was published are considered as valid.
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Introduction

This document describes a laboratory method of testing which gives a basis for assessment of the

effectiveness of a wood preservative against the Reticulitermes species of European termites. It allows

the determination of the concentration at which the product completely prevents attack by these insects

of impregnated wood of a susceptible species.

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 can be applied should be taken into account. It is

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

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 (see also Annex C for environmental, health and safety precautions).

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1 Scope

This document specifies a method for the determination of the toxic values of a wood preservative against

the Reticulitermes species of European termites .
This method is applicable to:
— water-insoluble chemicals which are being studied as active insecticides;

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

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

NOTE This method can be used in conjunction with an ageing procedure, for example EN 73 or EN 84.

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.

EN ISO 3696, Water for analytical laboratory use - Specification and test methods (ISO 3696)

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 (person or company providing the sample of wood preservative to be tested)

4 Principle

Impregnation of several sets of test specimens of susceptible wood with a series of solutions in which the

concentration of preservative is ranged in a given progression.

Exposure of these test specimens to specified colonies of Reticulitermes and assessment of the attack

suffered after exposure under fixed conditions and over a fixed period. In providing biological validation

The method can be applied not only to different species of Reticulitermes, but also to other species of the family

of the Rhinotermitidae, adapting the conditions of temperature and humidity where necessary to the specific

requirements of the species concerned.
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of individual species, it is essential that the locality of origin of each test termite species is given. The

description of the locality should at least include the district name.

Comparison of these results with those obtained with untreated and solvent or diluent-treated control

test specimens.
Derivation of the toxic values of the product under test.
5 Test materials
5.1 Biological material
Workers, soldiers and nymphs of an identified termite species of Reticulitermes.

The termite species and the locality of origin should be stated in the test report and their identification

should be proved.
The termites should be obtained from colonies reared as described in Annex B.
5.2 Products and reagents
5.2.1 Substrate for establishing the colonies. A choice of:

5.2.1.1 Fine white quartz sand consisting of grains of crystallized silica, very pure (90 % silica), and

free from any organic substances

5.2.1.2 A hydrated, laminar, aluminium-iron-magnesium silicate exfoliated to give particles of

3 3
1 mm to 3 mm with an apparent density of 80 kg/m to 90 kg/m

Particles of less than 1 mm shall be eliminated by sieving prior to use to ensure the absence of free water

and prevent any significant agglomeration of the particles.
5.2.1.3 Rigid polyurethane foam with open pores
3 3 2

NOTE Horticulture foam with mass per unit of volume of 14 kg/m and compressive strength of 0,02 N/mm

to 0,03 N/mm is suitable. It is advisable to cut the foam into sheets 15 mm thick.

5.2.2 Fumigant (if necessary) xylene, technical grade, mixed isomers
5.2.3 Water, complying with grade 3 of EN ISO 3696

5.2.4 Solvent or diluent, a suitable volatile liquid that will dissolve or dilute the preservative but does

not leave a residue in the wood which would have a toxic effect on the insect at the end of the conditioning

period
5.2.5 Filter paper, ordinary quality, medium-fast grade

In France Fontainebleau sand, of which more than 97 % of the particles are between 75 µm and 300 µm in size,

provides these features.
Determined in accordance with EN IS0 844.
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5.3 Apparatus

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

humidity of (70 ± 5) %

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

(65 ± 5) %

5.3.3 Laboratory work area, well ventilated, where treatment of the test specimens is carried out. It

is essential to follow safety procedures for handling flammable and toxic materials. Excessive exposure

of operators to solvents or their vapours should be avoided.

5.3.4 Testing chamber, protected from light, ventilated and controlled at (26 ± 2) °C and at a minimum

relative humidity of (70 ± 5) %

5.3.5 Treatment vessels, of a material that does not react with the preservative under test, for example

glass for organic products and polyethylene for salts containing fluorine

5.3.6 Drying vessel(s), capable of holding sets of three test specimens (7.5), provided with a close-

fitting cover and containing supports that will give minimum contact with treated test specimens to be

placed on them

The vessels and supports shall be of a material that does not react with the preservative under test, for

example glass for organic compounds and polyethylene for products containing fluorine.

5.3.7 Weights, to provide ballast for the test specimens

The weights shall not react with any materials with which they come in contact during the test.

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

to ensure the safety of the operator
5.3.9 Vacuum vessels, fitted with stopcocks, capable of receiving the treatment

5.3.10 Vacuum pump, fitted with a pressure gauge and capable of maintaining a pressure of 700 Pa

5.3.11 Instruments, adapted for termite manipulation (aspirator, forceps)

5.3.12 Test containers, suitable for holding the test specimens and of material resistant to the product

used, and fitted with perforated cover to provide a good exchange of air
2 2
Base area
35 cm to 60 cm
Minimum height 8,5 cm
3 3
Volume
500 cm to 1 000 cm

5.3.13 Glass rings or rings of other inert materials, ca. 20 mm to ca. 25 mm high, ca. 15 mm to ca.

25 mm in diameter and with a wall thickness of ca. 1 mm to ca. 2 mm
5.3.14 Protective gloves

The conditioning of test specimens after treatment can be carried out in the laboratory work area (5.3.3) provided

that this meets the conditions specified for the conditioning chamber (5.3.2).
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5.3.15 Ordinary laboratory equipment, including a balance capable of weighing to an accuracy of

0,01 g
6 Sampling

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

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

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

7 Test specimens
7.1 Species of wood
The reference species is Scots pine (Pinus sylvestris Linnaeus).

Additional tests can be carried out using other species but, if so, this should be stated in the test report.

7.2 Wood quality

The wood shall be free from visible cracks, stain, decay, insect damage and other defects. The wood shall

not have been water-stored, floated, chemically treated or steamed. The wood shall originate from trees

preferably felled in winter.
NOTE Wood that has been kiln dried at temperatures below 60 °C can be used.

The wood shall be exclusively sapwood containing little resin and having between 2,5 annual rings per

10 mm and eight annual rings per 10 mm. The proportion of latewood in the annual rings shall not exceed

30 % of the whole.

It is recommended to use test specimens of similar growth rate within a single test.

7.3 Provision of test specimens

Prepare planed strips having a cross-section of (25 ± 0,5) mm × (15 ± 0,5) mm removing a minimum of

2 mm from any surfaces exposed during drying. The longitudinal faces shall be parallel to the direction

of the grain. The annual rings shall have a contact angle of greater than 10° to the broad faces of the test

specimens. Make transverse cuts, neatly to give sharp edges and a fine-sawn finish to the end grain

surfaces, to give 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.
7.4 Dimensions of test specimens

The dimensions of each test specimen after reaching equilibrium in the conditioning chamber (5.3.2)

shall be (50 ± 0,5) mm × (25 ± 0,5) mm × (15 ± 0,5) mm.

For the purposes of calculating the mass of preservative retained per unit volume of wood (8.1.2.2) the

nominal volume of each test specimen shall be taken as 18,75 cm
Mark each test specimen so that it can be identified throughout the test.
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7.5 Number and distribution of test specimens
The test specimens shall be divided as follows:

a) treated test specimens: these are the test specimens which are impregnated and subject to attack by

Reticulitermes, use at least five test specimens for each concentration of the product;

b) untreated control test specimens for checking the virulence of the termite taken for the test: these

non-impregnated test specimens are subjected to attack by Reticulitermes; they are three in number;

c) solvent or diluent treated control test specimens subjected to attack by Reticulitermes; they are three

in number.
8 Procedure
8.1 Preparation of test specimens
8.1.1 Conditioning of test specimens prior to treatment

Allow the test specimens to condition in the conditioning chamber (5.3.2) for a minimum of two weeks.

8.1.2 Treatment of test specimens
8.1.2.1 Preparation fo treatment solutions
8.1.2.1.1 Solid preservatives

Water-soluble preservatives: dissolve the preservative in water (5.2.3) to the required concentration.

Non-water-soluble preservatives: dissolve the preservative in an appropriate solvent (5.2.4) to the

required concentration.
8.1.2.1.2 Liquid preservatives

If appropriate, use the preservative without further preparation other than any necessary stirring. If it is

a concentrate, dilute the preservative with the diluent to the required working concentration, using the

procedure specified by the supplier.

Prepare a series of at least five concentrations by mass, distributed evenly about the expected toxic

values. A solvent or diluent control, i.e. treatment at concentration = 0, shall also be used. If the

approximate toxic values are unknown, the concentrations shall form a widely spaced geometric

progression for a first test and a more closely spaced geometric or arithmetic progression for subsequent

tests.
All treatment solutions shall be freshly prepared.
8.1.2.2 Impregnation

Carry out impregnation in ascending order of concentration, starting with the solvent control

(concentration = 0). The following procedure ensures the required complete impregnation of test

specimens by the test solutions. For each concentration weigh each test specimen to the nearest 0,05 g,

and then stack the test specimens in one of the treatment vessels (5.3.5) so that as much of their face as

possible is exposed (e.g. by piling them crosswise). Ballast the stack of test specimens with weights (5.3.7)

to prevent them from floating later when the liquid is admitted.

Place each treatment vessel in one of the vacuum vessels (5.3.9) and reduce the pressure to 700 Pa.

Maintain this for 15 min. Observe the proper safety measures for vacuum vessels. After this period, close

the stopcock to the vacuum pump (5.3.10) and open the other stopcock to allow the solution of

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preservative to be drawn into the treatment vessel. Keep the test specimens covered completely by the

solution throughout the remainder of the impregnation process.

Next, admit air to bring the vacuum vessel back to atmospheric pressure, remove the treatment vessel

with its submerged test specimens from the vacuum vessel, cover it and leave it for 2 h, adding further

solution if necessary to keep the test specimens fully covered by the liquid.

After this impregnation treatment remove the test specimens one by one, remove the excess liquid from

their faces by lightly blotting with filter paper (5.2.5), and immediately weigh to the nearest 0,05 g.

In the case of water-soluble preservatives, for example salts and organic chemicals which are being

studied as active substances, calculate the mass of active matter retained by each test specimen from the

mass of solution absorbed and its concentration. When dealing with preservative formulations whose

constituents can be selectively absorbed by wood, it is necessary to carry out chemical analysis of the

solution before and after impregnation. Similarly, analysis is also recommended if very dilute solutions

are used.

In the case of organic formulations and organic water-dispersible formulations the retention is expressed

for each test specimen in terms of the corresponding mass of the formulation retained but, if a

concentration is supplied, the retention is expressed in terms of the solution prepared ready for use as

specified by the supplier.

Calculate the mass of preservative retained per unit volume of wood in kilograms per cubic metre, for

each test specimen.
8.1.3 Drying and conditioning of the test specimens after treatment

Drying and conditioning of the test specimens depend on the nature of the product under test and on the

solvent or diluent used. It can be necessary to modify the conditioning procedure but, if so, this should be

stated in the test report.

Arrange the impregnated test specimens treated with each preservative concentration on their narrow

faces, resting on two glass rods, not touching each other in the drying vessel (5.3.6). Place the cover on

the drying vessel. Place the drying vessel in the conditioning chamber (5.3.2). Invert the test specimens

twice each week during the subsequent drying period, temporarily removing the cover to perform these

operations.

To prevent mould growth on test specimens treated with water-diluted preservatives, place a small dish

containing the xylene (5.2.2) in the drying vessel (5.3.6).
During the first two weeks retain the cover on the drying vessel.

During the third week uncover the drying vessel progressively each day to allow the test specimens to

dry steadily.

From the beginning of the fourth week leave the drying vessel fully open. Drying shall be complete at the

end of the fourth week.

In the same way, place the test specimens impregnated with water-insoluble preservatives in the drying

vessel for one week and then open it gradually throughout the second week. From the beginning of the

third week leave the vessel fully open.

If, in case of slow drying products, the conditioning period is extended, the extended conditioning periods

shall be stated in the test report.
8.2 Exposure of the test specimens to the insects
8.2.1 Collecting and selecting the termites

Pick up the insects individually using the instrument (5.3.11). Make up groups of 250 workers, rejecting

insects which are moulting (indicated by the dull white colour of the abdomen) also those which appear

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to be wounded or remain motionless. To each group made up in this way add a number of soldiers

corresponding to the proportion found in the colony from which the workers were taken: add a

corresponding proportion of nymphs (1 % to 5 %).

The number of colonies to be prepared as indicated above is equal to the number of test specimens to be

subjected to attack by the termites.

If the required number of termites is more than that in a single culture, the control series and test series

shall contain the same number of groups from each colony. Termites from different colonies shall not be

mixed in a single group.
8.2.2 Instalaltion of the termites
8.2.2.1 With sand

In a separate test container (5.3.12), remoisten the adequate quantity of sand for the test by introducing

first the water (5.2.3) and then the sand (5.2.1.1) in the proportions of one volume of water to four

volumes of sand.

In each test container (5.3.12) form a layer of remoistened, non-compacted sand 40 mm to 60 mm thick.

At the (approximate) centre of the test container, place some wood from the original culture

(approximately 0,5 g) and push it down to the bottom of the test container.

In each test container, place a glass ring (5.3.13) against one of the vertical walls of the test container and

in the middle of this wall; place it in the substrate so that it just protrudes the surface. Distribute a group

of termites made up as indicated in 8.2.1 in each test container, spreading them carefully over the entire

substrate (see Figure 1).

Close each test container by means of its lid and place it in the testing chamber (5.3.4).

8.2.2.2 With aluminium-iron-magnesium silicate
Prepare enough a
...