EN 16718:2015

SLOVENSKI STANDARD
01-februar-2016
Les in lesni proizvodi - Delež celotnega organskega ogljika (TOC) v lesu in lesnih
proizvodih
Wood and wood based products - Dosage of the total organic carbon (TOC) in wood and
wood based products
Holz und Holzprodukte - Bestimmung des gesamten organischen Kohlenstoffs (TOC) in
Holz und Holzprodukten
Produits de préservation du bois et matériaux à base de bois - Dosage du carbone
organique total (COT) dans les bois et matériaux à base de bois
Ta slovenski standard je istoveten z: EN 16718:2015
ICS:
79.040 Les, hlodovina in žagan les Wood, sawlogs and sawn
timber
79.060.01 /HVQHSORãþHQDVSORãQR Wood-based panels in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 16718
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2015
EUROPÄISCHE NORM
ICS 79.060.01
English Version
Wood and wood based products - Dosage of the total
organic carbon (TOC) in wood and wood based products
Produits de préservation du bois et matériaux à base Holz und Holzprodukte - Bestimmung des gesamten
de bois - Dosage du carbone organique total (COT) organischen Kohlenstoffs (TOC) in Holz und
dans les bois et matériaux à base de bois Holzprodukten
This European Standard was approved by CEN on 12 September 2015.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, 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: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 16718:2015 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Principle . 7
5 Reagents and products . 8
6 Apparatus . 8
7 Procedure. 8
7.1 Preparation of the sample . 8
7.2 Water content . 8
7.3 Dosage . 9
7.3.1 General . 9
7.3.2 TC dosage . 9
7.3.3 TIC dosage . 9
7.4 Calibration . 9
7.5 Control measurements . 10
7.6 Evaluation . 10
7.7 C measurement by IRMS (Isotope Ratio Mass Spectrometer) . 11
7.7.1 Material and methods . 11
7.7.2 C isotope . 12
7.7.3 O isotope . 12
7.7.4 H isotope (Deuterium) . 12
7.7.5 N Isotopes . 12
13 18 2
7.7.6 Multi-isotopic determinations: C, O and H in wood and tree . 12
8 Performance characteristics . 13
9 Test report . 13
Annex A (informative) Results of the validation method . 14
A.1 General . 14
A.2 Response function . 14
A.2.1 General . 14
A.2.2 Total carbon . 15
A.2.3 Inorganic carbon . 16
A.3 Trueness . 17
A.3.1 General . 17
A.3.2 Total carbon . 18
A.3.3 Inorganic carbon . 18
A.4 Precision . 18
A.4.1 General . 18
A.4.2 Total carbon . 18
A.4.3 Inorganic carbon . 20
A.5 Measurement uncertainty . 21
A.5.1 General . 21
A.5.2 Total carbon. 21
A.5.3 Inorganic carbon . 22
A.6 Accuracy . 22
A.6.1 General . 22
A.6.2 Total carbon. 22
A.6.3 Inorganic carbon . 24
A.7 Linearity of results . 25
A.7.1 Total carbon. 25
A.7.2 Inorganic carbon . 26
A.8 Quantification limit and dosage interval . 27
A.8.1 Total carbon. 27
A.8.2 Inorganic carbon . 27
A.9 Conclusion . 27
Annex B (informative) Measurements on wood species and wood-based materials . 28
Bibliography . 29

European foreword
This document (EN 16718:2015) 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 2016, and conflicting national standards shall be
withdrawn at the latest by May 2016.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: 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, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Introduction
Bio-based products from forestry and agriculture have a long history of application. The last decades
have seen the emergence of new bio-based products in the market. Acknowledging the need for
common standards for bio-based products, the European Commission issued mandate M/492, resulting
in a series of standards developed by CEN/TC 411.
For business to business transactions, claims which are relevant to describe characteristics of bio-based
products in a business to business environment will be given in the near future. Data are by
consequence required to generate and transfer information in the industrial chain and/or as an input
for product specific standards and certification schemes.
The work to be done by the CEN/TC 411/WG 3 concerns the determination of the bio-based carbon in
order to determine the level of bio-based content of a product or materials. A document
(CEN/TR 16721) has been prepared by Technical Committee CEN/TC 411 “Bio-based products”, and
describes a list of methods and an “overview of methods to determine the bio-based content and related
methods” for Bio-based products.
As part of the task force of CEN/TC 175, devoted to carbon foot printing and LCA, a European Standard
was published on the simplified calculation of the amount of biomass carbon stored in wood (using
50 % of the anhydrous wood mass): EN 16449.
This standard EN 16718 describes the methods based on analytical measurements. These methods can
be considered as complementary to the radiocarbon based method and methods based on evaluation by
calculation (mass balance approaches). One of these analytical methods is a method based on
measurement of stable isotopic ratio present in biomass in order to determine the biomass content of
the product.
The development of this method described in this report is ongoing with close collaboration between
FCBA and the “Institute des Sciences Analytiques” CNRS in order to determine the bio-based content of
wood raw materials, glues and panels made with these raw materials for end use manufactured
products with this new method. The objective is to propose correlated analysis (with the TOC method
proposed by FCBA) to determine the carbon content to purpose a quick and low cost method easy to
handle.
References:
— http://www.biobasedeconomy.eu/standardisation/cen-tc411/
— http://www2.afnor.org/espace_normalisation/structure.aspx?commid=86489
The tests that have resulted in the specification of this document were performed in the context of work
conducted by the FCBA [timber certification body] Technological Institute aimed at determining a
method for supplying data on organic carbon contents that could be used to calculate carbon balances.
The storage of biomass carbon in wood-based products is the preservation of the carbon absorbed by
the tree from atmospheric CO through photosynthesis.
The carbon thus captured in the material is of benefit to the climate throughout the lifespan of the
product, which can be several dozen years for a construction product, for example. The French Standard
NF P01-010 (2004), which lays out the format of environmental and health statements (FDES) for
construction products, provides the option of indicating the following supplementary information, in
addition to the “Climate change” indicator, which is calculated from the flows of greenhouse gases
associated with the product life cycle: “for some construction products (e.g. plant-based products), CO2
storage during the “service life” stage can be given if measurements are taken based on standardized
test methods.”
Furthermore, the Guide to Best Practices on environmental labelling of mass-market consumer
products (BP X30-323) includes in Annex G: “Carbon accounting integrating time lag” which also
requires knowledge of the biomass carbon contents of the products.
The purpose of this document is therefore to propose a laboratory measurement method of the amount
of biomass carbon that will provide values of carbon or CO equivalent stored in wood-based products,
with the aim to integrate this information in the environmental statements of these products according
to the texts referenced above.
While measurement is not systematically necessary for solid wood products, for example, given the
common knowledge on the densities of the various wood species and on the proportion of carbon
contained in wood, this experimental measurement may prove to be necessary for products made of
wood-based composite materials.
The organic carbon contained in wood and wood-based materials is found in several different forms.
Cumulative measurements, such as total organic carbon (TOC), need to be used. Isotopic ratio enables
the differentiation between synthetic and natural products. IRMS (Isotope Ratio Mass Spectrometer) is
a complementary method to the TOC method by an identification of the isotope C: both techniques are
necessary to give reliable data on a bio-based content on a wood based material such as panel, board,
and woods containing chemicals in general. A study is currently in progress in France on wood based
materials: the results will enable to improve this present document and to give data with multi-isotopic
13 15 2 18
determinations ( C, N, H, O).
1 Scope
This European Standard describes a method for determining total organic carbon by calculating the
difference between the results of measurements of total carbon (TC) and total inorganic carbon (TIC).
The identification of the bio-based content given by the stable isotopes such as C is described also.
This method is applicable to all wood species, wood-based materials (panels, plywood, wood-polymer,
etc.) and woods containing chemicals in general.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 13183-1, Moisture content of a piece of sawn timber — Part 1: Determination by oven dry method
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
total carbon
TC
amount of carbon found in waste, in organic, inorganic and elemental-state forms
3.2
total inorganic carbon
TIC
amount of carbon released as carbon dioxide through acidification
3.3
total organic carbon
TOC
carbon that is transformed into carbon dioxide through combustion and not released through
acidification as carbon dioxide
Note 1 to entry: The definitions given above are only applicable in this document and only partly overlap the
scientific definitions of TC, TOC and TIC.
4 Principle
In this procedure, TOC is obtained by subtraction between the measurement results of TC and TIC.
The total carbon (TC) present in the undried sample is transformed into carbon dioxide through
combustion in a flow of gas that contains oxygen and is free of carbon dioxide. To ensure combustion is
total, catalysers and/or modifiers can be used. The amount of carbon dioxide released is measured
using infrared spectrometry, gravimetry, coulometry, conductometry, thermal conductivity detection or
flame ionization detection after reduction to methane, or any other appropriate technique.
The TIC is determined separately using another sub-sample, through acidification and purging of the
released carbon dioxide, which is then measured using one of the techniques mentioned above.
The C identification by IRMS is described in 7.7. This protocol is able also to work on other isotopes:
15 2 18
N, H and O, which could be useful for complex materials containing wood.
5 Reagents and products
All the reagents used shall be of analytical grade at least and suitable for their specific uses. Hygroscopic
products shall be kept in a dessicator.
5.1 Glucose, C H O .
6 12 6
5.2 Anhydrous sodium carbonate, Na CO .
2 3
5.3 Non-oxidizing mineral acid used to release the carbon dioxide, e.g. phosphoric acid H PO ,
3 4
(m = 85 %).
5.4 Synthetic air, nitrogen, oxygen, argon, free of carbon dioxide and organic impurities,
according to the instructions supplied by the machine manufacturer.
6 Apparatus
6.1 Homogenization device, such as mixers, stirrers.
6.2 Analytical balance accurate to at least 0,5 % of test portion weight.
6.3 Apparatus for dosing carbon in solid matter, along with its accessories.
6.4 Purging device for dosing TIC.
6.5 Mixer mill.
7 Procedure
7.1 Preparation of the sample
Before the sample preparation, the sampling program shall be properly designed in accordance with the
context of the testing and objectives.
The samples to be analysed should be as homogeneous as possible and undried.
The samples of wood or wood-based materials can be directly ground (avoiding any heating) and
reduced to powder, preferably with a particle size below 500 μm. The samples are ground in their
entire thickness.
The samples that contain negligible concentrations (taking into account the accuracy of the method
used) of volatile compounds other than water can be dried at 105 °C before they are homogenized.
7.2 Water content
The determination of moisture content shall be carried out using a different test portion. It can be
calculated from the dry matter mass, determined according to EN 13183-1.
NOTE Any other determination method (e.g. with a desiccator’s balance) can be used if it has been previously
validated.
7.3 Dosage
7.3.1 General
This document does not give any recommendations for the apparatus and its mode of operation. The
operating conditions should be selected and verified according to the instructions supplied by the
manufacturer.
It is advisable to select a test portion with the greatest mass possible, making sure that the amount of
carbon dioxide released is within the apparatus measurement range and the calibration range.
7.3.2 TC dosage
The sample, prepared according to 7.1, is weighed in an appropriate container, i.e. inert and not liable to
interact during the carbon content analysis reaction or to contain carbon in any form whatsoever
(scoop or crucible made of e.g. ceramic, silica glass, platinum or tin). The container can be previously
conditioned by heating (in a muffle furnace or in the analyser itself) to minimize blank carbon values.
The sample is burned or broken down in a carrier gas current that contains oxygen.
The combustion temperature shall be sufficiently high to transform all the carbon into carbon dioxide.
For samples containing carbonates that are difficult to break down, such as barium carbonate, carbon
dioxide release can be improved by increasing the temperature or using modifiers (e.g. tin, copper).
The temperature range of commercially available devices is between 900 °C and 1 500 °C.
During combustion of the reactive samples, any detonation or production of smoke can be avoided by
covering the sample with an inert material (e.g. siliceous sand).
The carbon dioxide released while gas is being discharged is measured using the detection method
described in chapter 4, and expressed as carbon.
7.3.3 TIC dosage
The
...