oSIST prEN 15119-1:2026

• Abstract:

  This document specifies a laboratory method for obtaining water samples from preservative treated wood exposed out of ground contact (wood held in the storage yard after treatment and which has been in conditions designed to simulate outdoor, out of ground contact situations), at increasing time intervals after exposure.

• Status: Not Published
• Public Enquiry End Date: 30-Oct-2026
• ICS: 13.020.30 - Environmental impact assessment
• ICS: 71.100.50 - Wood-protecting chemicals
• ICS: 79.040 - Wood, sawlogs and sawn timber
• Technical Committee: LLZ - Les, lesni izdelki in zaščita lesa
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 21-Aug-2026
• Due Date: 08-Jan-2027
• Ref Project: prEN 15119-1 - Biological durability of wood and wood-based products - Determination of emissions from preservative treated wood to the environment - Part 1: Wood held in the storage yard after treatment and wooden commodities exposed in Use Class 3 (not covered, not in contact with the ground) - Laboratory method

• Revises: SIST EN 15119-1:2025 - Durability of wood and wood-based products - Determination of emissions from preservative treated wood to the environment - Part 1: Wood held in the storage yard after treatment and wooden commodities exposed in Use Class 3 (not covered, not in contact with the ground) - Laboratory method
• Effective Date: 13-Feb-2026

oSIST prEN 15119-1:2026 is SIST's publication of the draft European Standard prEN 15119-1, prepared by CEN/TC 38. It specifies a laboratory method for collecting water samples from preservative treated wood exposed out of ground contact, including wood held in the storage yard after treatment and wooden commodities in Use Class 3, so the leachate can be analysed for environmental risk assessment.

What does oSIST prEN 15119-1:2026 specify?

oSIST prEN 15119-1:2026 specifies a laboratory method for obtaining water samples from preservative treated wood exposed above ground and not in contact with the ground. The method is intended to simulate outdoor wetting and drying, so the emissions from treated wood can be measured over time.

The document is organized into five clauses and one informative annex:

Annex	What it covers
Annex A	Recording forms for the test results

Clause 1 gives the scope, Clause 2 lists the normative references, Clause 3 covers terms and definitions, Clause 4 gives the test method, and Clause 5 gives the test report content. Annex A provides example recording forms for routine test use.

What are the key requirements of oSIST prEN 15119-1:2026?

Clause 4.1 and 4.7.4 set out two immersion regimes that simulate rainfall on treated wood: 3 × 1 min with drying between events, or 2 × 1 h with a longer drying period. The test days are fixed at 1, 3, 5, 8, 10, 12, 15, 17 and 19. In practice, the laboratory must choose a regime that matches the intended use and explain why it is appropriate.

How does the method simulate real exposure?

Clause 4.2 says the method uses simulated wetting and drying to model rainfall-driven leaching. The leachate from each immersion day is collected and can be analysed chemically or tested for ecotoxicity. This matters because the result is meant to support environmental risk assessment, not only to show that material has been washed.

Clause 4.1 also states that the treated wood should be representative of commercially treated wood and that the post-treatment conditioning must be stated. That means the test has to reflect the actual product as used, including the treatment route and any surface treatment such as paint when relevant.

What specimens and apparatus are required?

Clause 4.6 requires wood test specimens of at least 25 mm by 50 mm by 15 mm, with 100 % sapwood, plain sawn faces and no sanding. The specimens must be identified throughout the test. This keeps the exposed surface consistent and avoids extra variability from the sample preparation.

Clause 4.6.3 requires treated specimens in two immersion containers and untreated specimens as a control, with at least 200 cm² of exposed surface per container. Clause 4.5.1 requires an inert immersion container with a water-to-surface-area ratio of 25 L per m² of exposed surface area, and the container is covered to limit evaporation. In practice, the lab needs enough replicate material to compare treated samples with untreated background levels.

Clause 4.4 and 4.5 also set the conditions for water, storage and equipment. The test water should normally have pH 5 to 7 and a temperature of (20 ± 2) °C, and the leachates should be stored cold, typically below -18 °C, to limit degradation before analysis. This is important because sample handling can change the measured emission.

How are results calculated and reported?

Clause 4.8 converts the analytical results into emission flux in milligrams per square metre per day. Background from untreated wood, and if needed from control water, is subtracted before the final emission value is reported. This gives a result that can be compared across products and exposure times.

Clause 5 requires the report to identify the preservative, the wood species and density, the retention or loading, the application method, conditioning, sealant, any later surface treatment, the immersion details, analytical samples, deviations and unusual observations. Annex A provides the recording forms used to capture those data consistently.

Who uses oSIST prEN 15119-1:2026?

oSIST prEN 15119-1:2026 is used by test laboratories, wood preservative suppliers, and manufacturers of treated wood or wooden commodities that will be used in Use Class 3. It is also used by environmental risk assessors and buyers or quality teams who need leaching data that can be traced back to a defined test method.

The document is especially relevant where rainfall runoff from stored treated wood or exposed commodities may affect surface water or soil. That makes it useful in product approval, technical file preparation, and comparative testing between treatment systems.

What changed in oSIST prEN 15119-1:2026 from the previous edition?

prEN 15119-1:2026 will supersede EN 15119-1:2025. The introduction states that test results obtained with earlier versions of the method remain valid.

Which standards are used with oSIST prEN 15119-1:2026?

• EN ISO 5667-3 - gives guidance for preservation and handling of water samples.
• prEN 18381 - gives the specimen preparation method before leaching testing.
• EN 335 - defines the Use Classes referred to for Use Class 3 exposure.
• EN ISO 3696 - provides the water quality specification used for the test water.
• EN 15119-2 - the companion part for wooden commodities in Use Class 4 or 5.

What does the oSIST prEN 15119-1:2026 document contain?

The document contains the test principle, quality criteria, equipment requirements, specimen preparation, immersion procedures, calculation of emission rates, and reporting rules. It also describes how untreated controls and control water are used to identify background levels.

Annex A gives example recording forms for both immersion regimes. Those forms support routine test-house work by structuring the specimen data, immersion timing, analytical results and calculated emission values in one place.

SLOVENSKI STANDARD
01-oktober-2026
Biološka odpornost lesa in lesnih proizvodov - Ugotavljanje emisij iz zaščitenega
lesa v okolje - 1. del: Sveže zaščiten les v skladiščih in lesni izdelki, izpostavljeni 3.
razredu uporabe (nepokrita uporaba, ni v stiku z zemljo) - Laboratorijska metoda
Biological durability of wood and wood-based products - Determination of emissions from
preservative treated wood to the environment - Part 1: Wood held in the storage yard
after treatment and wooden commodities exposed in Use Class 3 (not covered, not in
contact with the ground) - Laboratory method
Biologische Dauerhaftigkeit von Holz und Holzprodukten - Abschätzung von Emissionen
von mit Holzschutzmitteln behandeltem Holz an die Umwelt– Teil1: Holz auf dem
Lagerplatz nach der Behandlung und Holzprodukte in Gebrauchsklasse3 (nicht
abgedeckt, ohne Erdkontakt) - Laborverfahren
Durabilité biologique du bois et des matériaux à base de bois - Estimation des émissions
dans l’environnement du bois traité avec des produits de préservation - Partie 1: Bois
stocké en dépôt après traitement et articles en bois exposés en classe d’emploi 3 (non
couverts, non en contact avec le sol) - Méthode de laboratoire
Ta slovenski standard je istoveten z: prEN 15119-1
ICS:
13.020.30 Ocenjevanje vpliva na okolje Environmental impact
assessment
71.100.50 Kemikalije za zaščito lesa Wood-protecting chemicals
79.040 Les, hlodovina in žagan les Wood, sawlogs and sawn
timber
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2026
ICS 71.100.50 Will supersede EN 15119-1:2025
English Version
Biological durability of wood and wood-based products -
Determination of emissions from preservative treated
wood to the environment - Part 1: Wood held in the
storage yard after treatment and wooden commodities
exposed in Use Class 3 (not covered, not in contact with
the ground) - Laboratory method
Durabilité biologique du bois et des matériaux à base Biologische Dauerhaftigkeit von Holz und
de bois - Estimation des émissions dans Holzprodukten- Abschätzung von Emissionen von mit
l'environnement du bois traité avec des produits de Holzschutzmitteln behandeltem Holz an die Umwelt-
préservation - Partie 1: Bois stocké en dépôt après Teil1: Holz auf dem Lagerplatz nach der Behandlung
traitement et articles en bois exposés en classe und Holzprodukte in Gebrauchsklasse3 (nicht
d'emploi 3 (non couverts, non en contact avec le sol) - abgedeckt, ohne Erdkontakt) - Laborverfahren
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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 15119-1:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test method . 5
4.1 General considerations . 5
4.2 Principle . 6
4.3 Quality criteria . 6
4.3.1 Accuracy . 6
4.3.2 Reproducibility . 7
4.4 Product and reagent . 7
4.4.1 Water . 7
4.4.2 Preservative . 7
4.5 Apparatus . 7
4.5.1 Immersion container . 7
4.5.2 Assembly for test specimens . 7
4.5.3 Vessel for receiving water . 7
4.5.4 Preservative treatment . 8
4.5.5 Balance . 8
4.5.6 Safety equipment and protection clothing . 8
4.5.7 Refrigerator/freezer . 8
4.5.8 Chemical analysis equipment . 8
4.6 Test specimens . 8
4.6.1 General . 8
4.6.2 Size of test specimens . 8
4.6.3 Number of test specimens . 8
4.7 Procedure. 9
4.7.1 General . 9
4.7.2 Conditioning of the test specimens after treatment . 9
4.7.3 Preparation and selection of test specimens . 9
4.7.4 Immersion method . 9
4.8 Expressions of results .11
4.8.1 Chemical analysis .11
4.8.2 Chemical analysis: bulked samples .11
4.8.3 Recording .11
4.9 Evaluation of water samples other than by chemical analysis, e.g. ecotoxicity test .11
5 Test report .12
Annex A (informative) Recording forms .13
Bibliography .16

European foreword
This document (prEN 15119-1:2026) has been prepared by Technical Committee CEN/TC 38 “Biological
durability of wood and wood-based products”, the secretariat of which is held by SIS.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 15119-1:2025.
EN 15119 is composed of the following parts:
— Part 1: Wood held in the storage yard after treatment and wooden commodities exposed in Use Class 3
(not covered, not in contact with the ground) — Laboratory method
— Part 2: Wooden commodities exposed in Use Class 4 or 5 (in contact with the ground, fresh water or sea
water) — Laboratory method
Introduction
Test results obtained with earlier versions of this method (i.e. EN 15119-1:2025) are still valid.
The emissions from preservative treated wood into the environment need to be quantified to enable an
environmental risk assessment to be made of the treated wood. This document specifies a laboratory
method for the determination of emissions by leaching from preservative treated wood where the
preservative treated wood is not covered and not in contact with the ground or the water. There are two
situations in this case where such emissions could enter the environment:
a) emissions from preservative treated wood stored outside in the storage yard of a preservative
treatment site. Rain falling on the treated wood could produce emissions that run off into surface
water and / or soil;
b) emissions from treated wood used in commodities exposed in Use Class 3. This is the situation in
which the wood or wood-based product is not covered and not in contact with the ground. It is either
continually exposed to the weather or is protected from the weather but subject to frequent wetting.
Use classes are specified in EN 335 and categorize the biological hazard to which the treated
commodity will be subjected. The Use Classes also specify the situation in which the treated
commodity is used and determine the environmental compartments (air, water, soil) which are
potentially at risk from the preservative treated wood. Rain falling on treated wood in Use Class 3
could produce emissions that run off into surface water and/ or soil.
The method is a laboratory procedure for obtaining water samples (leachate) from treated wood exposed
out of ground contact, at time intervals after exposure. The quantities of emissions in the leachate are
related to the surface area of the wood and the length of exposure, to estimate a flux in milligrams per
square metre per day. The flux after increasing periods of exposure (e.g. 1 year, 10 years) can be
estimated.
NOTE The leachate can also be tested for eco-toxicological effects.
The quantity of emissions can be used in an environmental risk assessment of the treated wood.
The test can be applied to wood treated using a penetrating process or superficial application (brush,
spray or dipping), or to treated wood which has an additional surface treatment (e.g. paint that is applied
as a requirement for commercial use).
1 Scope
This document specifies a laboratory method for obtaining water samples from preservative treated
wood exposed out of ground contact (wood held in the storage yard after treatment and which has been
in conditions designed to simulate outdoor, out of ground contact situations), at increasing time intervals
after exposure.
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 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
(ISO 5667-3)
prEN 18381, Biological durability of wood and wood-based products - Preparation of wood and wood-based
material specimens before leaching testing (number to be updated)
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
4 Test method
4.1 General considerations
The principal agent for causing emissions from wood during open-air storage in the yard and in
Use Class 3 is rainfall. Wood exposed in above ground situations is subjected to intermittent wetting by
rainfall and drying of the wood surface between the rainfall events. These wetting and drying cycles are
simulated by the method described in this document. It is assumed that emissions obtained by short-term
immersion in water are indicative of the emissions which will occur during exposure to rainfall.
The wood, in the case of wood treated with a wood preservative, shall be representative of commercially
treated wood. It shall be treated in accordance with the preservative manufacturer’s instructions and in
compliance with appropriate standards and specifications. The parameters for post-treatment
conditioning of the wood prior to the commencement of the test shall be stated.
The wood samples used shall be representative of the commodities used.
The composition, amount, pH value and the physical form of rainfall are important in determining the
quantity, content and nature of emissions from wood. However, simulating a realistic rainfall regime in
the laboratory is time-consuming, expensive and is likely to lack reproducibility, accuracy, precision and
reliability.
Two main immersion regimes are recommended as follows:
1. The 3 × 1 min immersion regime: A 1 min immersion in water of the treated test specimens to
simulate exposure to a rainfall event. There are three immersions or rainfall events per day, with test
specimens allowed to dry for 3 h between immersions simulating the wetting and drying cycle of
natural exposure situations. The days of rainfall are set for 1, 3, 5, 8, 10, 12, 15, 17 and 19 days.
NOTE 1 The OECD Emission Scenarios for Wood Preservatives 2013 (see bibliography) that are applied for
the authorization procedure of the European BPR are based on the assumptions, that the total amount of
rainfall per year is 700 mm. The daily regime is intended to produce the same moisture content on the surface
of the wood, and the same moisture content profile in the wood, and thus the same emission, as wood in a real
exposure situation on a day during which rain occurs. It is intended that a 3 × 1 min dip, every third day, will
give the same moisture content cycle in the wood, and the same emission from the wood, as exposure under
real conditions. If the dipping and drying regime is continued for one year, the emission quantity and rate
would be the same as the emission obtained from wood after exposure in a real situation in a region of Europe
where there is 700 mm of rain per year, with rain events occurring on 260 days of the year.
2. The 2 × 1 h immersion regime: A 1 h immersion in water of the treated test specimens to simulate
exposure to a rainfall event. There are two immersions or rainfall events per day, with test specimens
allowed to dry for 4 h between immersions simulating the wetting and drying cycle of vertical natural
exposure situations. The days of rainfall are set for 1, 3, 5, 8, 10, 12, 15, 17 and 19 days.
The applicant shall provide adequate discussion of the conditions of these regimes (e.g. purpose is to
estimate emissions from wood that is treated and then exposed vertically or horizontally) for data to be
acceptable when using these regimes.
NOTE 2 The OECD 107 (see in Bibliography) proposes a third immersion regime (1 × 2 h). It was decided not to
retain this option in this document.
4.2 Principle
To simulate the emission of wood preservatives from wood exposed to rain water, a simulated wetting
and drying process is employed. This process is used to simulate the wetting and drying of natural
exposure situations. The water (leachate) from each immersion day is collected and analysed chemically.
It is suitable for ecotoxicity testing. Emission rates in milligrams per square metre per day are calculated
from analytical results.
A system with untreated wood specimens provides background levels for leachates from wood. Tests
with untreated samples can be discontinued if there is no background detected in the first three data
points.
Recording forms are given in Annex A.
4.3 Quality criteria
4.3.1 Accuracy
The performance of the analytical method should be determined before conducting the test:
1) accuracy;
2) specificity;
3) limit of detection;
4) limit of quantification.
The testing is carried out with untreated references and with controlled water.
NOTE EN ISO 5667-3 gives guidance on the preservation and handling of water samples.
4.3.2 Reproducibility
Two water samples are collected and analysed and the mean value is taken as the emission value. The
reproducibility of the results within one laboratory and between different laboratories depends upon the
immersion regime and the wood used as test specimens.
4.4 Produc
...