CEN/TS 17196:2018

Construction products: Assessment of release of dangerous substances - Digestion by aqua regia for subsequent analysis of inorganic substances

This Technical Specification specifies methods for obtaining the aqua regia digestible content of construction products. Solutions produced by this method are for analysis by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled spectrometry (ICP-OES) for the following 67 elements:
Aluminium (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), bismuth (Bi), boron (B), cadmium (Cd), calcium (Ca), cerium (Ce), cesium (Cs), chromium (Cr), cobalt (Co), copper (Cu), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), gallium (Ga), germanium (Ge), gold (Au), hafnium (Hf), holmium (Ho), indium (In), iridium (Ir), iron (Fe), lanthanum (La), lead (Pb), lithium (Li), lutetium (Lu), magnesium (Mg), manganese (Mn), mercury (Hg), molybdenum (Mo), neodymium (Nd), nickel (Ni), palladium (Pd), phosphorus (P), platinum (Pt), potassium (K), praseodymium (Pr), rubidium (Rb), rhenium (Re), rhodium (Rh), ruthenium (Ru), samarium (Sm), scandium (Sc), selenium (Se), silicon (Si), silver (Ag), sodium (Na), strontium (Sr), sulphur (S), tellurium (Te), terbium (Tb), thallium (Tl), thorium (Th), thulium (Tm), tin (Sn), titanium (Ti), tungsten (W), uranium (U), vanadium (V), ytterbium (Yb), yttrium (Y), zinc (Zn), and zirconium (Zr).
Solutions produced by the methods are suitable for analysis by cold vapour atomic absorption or fluorescent spectrometry (CV-AAS, CV-AFS), for mercury (Hg).
The method in this Technical Specification is applicable to construction products.
Digestion with aqua regia will not necessarily accomplish total decomposition of the sample. The extracted analyte concentrations may not necessarily reflect the total content in the sample.
NOTE   Construction products include e.g. mineral-based products (S); bituminous products (B); metals (M); wood-based products (W); plastics and rubbers (P); sealants and adhesives (A); paints and coatings (C), see also CEN/TR 16045.

Bauprodukte - Bewertung der Freisetzung von gefährlichen Stoffen - Königswasser-Aufschluss zur anschließenden Analyse von anorganischen Stoffen

Diese Technische Spezifikation legt Verfahren zur Gewinnung des mit Königswasser aufschließbaren Anteils von Bauprodukten fest. In den Lösungen, die nach diesem Verfahren hergestellt wurden, können mittels Massenspektrometrie mit induktiv gekoppeltem Plasma (ICP-MS) oder mittels optischer Emissionspektrometrie mit induktiv gekoppeltem Plasma (ICP-OES) die folgenden 67 Elemente analysiert werden:
Aluminium (Al), Antimon (Sb), Arsen (As), Barium (Ba), Beryllium (Be), Bismut (Bi), Blei (Pb), Bor (B), Cadmium (Cd), Calcium (Ca), Cäsium (Cs), Cer (Ce), Chrom (Cr), Cobalt (Co), Dysprosium (Dy), Eisen (Fe), Erbium (Er), Europium (Eu), Gadolinium (Gd), Gallium (Ga), Germanium (Ge), Gold (Au), Hafnium (Hf), Holmium (Ho), Indium (In), Iridium (Ir), Kalium (K), Kupfer (Cu), Lanthan (La), Lithium (Li), Lutetium (Lu), Magnesium (Mg), Mangan (Mn), Molybdän (Mo), Natrium (Na), Neodym (Nd), Nickel (Ni), Palladium (Pd), Phosphor (P), Platin (Pt), Praseodym (Pr), Quecksilber (Hg), Rubidium (Rb), Rhenium (Re), Rhodium (Rh), Ruthenium (Ru), Samarium (Sm), Scandium (Sc), Schwefel (S), Selen (Se), Silber (Ag), Silizium (Si), Strontium (Sr), Tellur (Te), Terbium (Tb), Thallium (Tl), Thorium (Th), Thulium (Tm), Titan (Ti), Uran (U), Vanadium (V), Wolfram (W), Ytterbium (Yb), Yttrium (Y), Zink (Zn), Zinn (Sn) und Zirconium (Zr).
Durch die Verfahren erstellte Lösungen sind für die Analyse von Quecksilber (Hg) mittels Kaltdampf-Atomabsorptions- oder Fluoreszenzspektrometrie (CV-AAS, CV-AFS) geeignet.
Die in dieser Technischen Spezifikation beschriebenen Verfahren sind für Bauprodukte geeignet.
Der Aufschluss mit Königswasser wird die Probe nicht unbedingt völlig zersetzen. Die extrahierten Analytkonzentrationen können unter Umständen nicht den Gesamtgehalt in der Probe wiedergeben.
ANMERKUNG   Bauprodukte umfassen z. B. mineralische Produkte (S), bituminöse Produkte (B), Metalle (M), Holzprodukte (W), Kunststoffe und Gummi (P), Dichtstoffe und Kleber (A), Farben und Beschichtungen (C), siehe auch CEN/TR 16045.

Produits de construction - Evaluation de l’émission de substances dangereuses - Digestion par l’eau régale pour une analyse ultérieure de substances inorganiques

Gradbeni proizvodi - Ocenjevanje sproščanja nevarnih snovi - Razklop z zlatotopko za analizo anorganskih snovi

Ta tehnična specifikacija določa metodo za razklop gradbenih proizvodov za analizo vsebnosti anorganskih snovi. Metoda temelji na uporabi zlatotopke. Raztopine, pridobljene s to metodo, so primerne za analizo z npr. masno spektrometrijo z induktivno sklopljeno plazmo (ICP-MS) in emisijsko spektrometrijo z induktivno sklopljeno plazmo (ICP-OES), atomsko absorpcijsko spektrometrijo (CVAAS, CVAFS) za naslednje elemente: aluminij, antimon, arzen, barij, berilij, bizmut, bor, kadmij, kalcij, cerij, krom, kobalt, baker, železo, lantan, svinec, litij, magnezij, mangan, živo srebro, molibden, neodim, nikelj, fosfor, kalij, prazeodim, samarij, skandij, selen, silicij, srebro, natrij, stroncij, žveplo, telurij, talij, torij, kositer, titan, volfram, uran, vanadij, cink in cirkonij. OPOMBA: Gradbeni proizvodi vključujejo npr. mineralne proizvode (S), bitumenske proizvode (B), kovine (M), lesne proizvode (W), plastične mase in gume (P), tesnila in lepila (A), barve in premaze (C), glej tudi CEN/TR 16045.

General Information

• Status: Withdrawn
• Publication Date: 17-Jul-2018
• Withdrawal Date: 13-Apr-2025
• ICS: 91.100.01 - Construction materials in general
• Technical Committee: CEN/TC 351 - Construction Products - Assessment of release of dangerous substances
• Drafting Committee: CEN/TC 351/WG 5 - Content and eluate analysis in construction products
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Start Date: 22-Nov-2023
• Completion Date: 14-Apr-2025
• 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
• Directive: 88/609/EEC - Limitation of emissions of certain pollutants into the air from large combustion plants
• Mandate: M/366 - Concerning the execution of standardisation work for the development of horizontal standardised assessment methods for harmonized approcaches relating to dangerous substances under the construction products directive (CPD)
• Ref Project: SIST-TS CEN/TS 17196:2019 - Construction products - Assessment of release of dangerous substances - Digestion by aqua regia for subsequent analysis of inorganic substances

Relations

• Replaced By: EN 17196:2023 - Construction products: Assessment of release of dangerous substances - Digestion by aqua regia for subsequent analysis of inorganic substances
• Effective Date: 19-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2019
*UDGEHQLSURL]YRGL2FHQMHYDQMHVSURãþDQMDQHYDUQLKVQRYL5D]NORS]
]ODWRWRSNR]DDQDOL]RDQRUJDQVNLKVQRYL
Construction products - Assessment of release of dangerous substances - Digestion by
aqua regia for subsequent analysis of inorganic substances
Bauprodukte - Bewertung der Freisetzung von gefährlichen Stoffen - Königswasser-
Aufschluss zur anschließenden Analyse von anorganischen Stoffen
Produits de construction - Evaluation de l’émission de substances dangereuses -
Digestion par l’eau régale pour une analyse ultérieure de substances inorganiques
Ta slovenski standard je istoveten z: CEN/TS 17196:2018
ICS:
13.020.99 Drugi standardi v zvezi z Other standards related to
varstvom okolja environmental protection
91.100.01 Gradbeni materiali na Construction materials in
splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN/TS 17196
TECHNICAL SPECIFICATION
SPÉCIFICATION TECHNIQUE
July 2018
TECHNISCHE SPEZIFIKATION
ICS 91.100.01
English Version
Construction products: Assessment of release of
dangerous substances - Digestion by aqua regia for
subsequent analysis of inorganic substances
Produits de construction - Evaluation de l'émission de Bauprodukte - Bewertung der Freisetzung von
substances dangereuses - Digestion par l'eau régale gefährlichen Stoffen - Königswasser-Aufschluss zur
pour une analyse ultérieure de substances anschließenden Analyse von anorganischen Stoffen
inorganiques
This Technical Specification (CEN/TS) was approved by CEN on 9 March 2018 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to
submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS
available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in
parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 17196:2018 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 Symbols and abbreviations . 7
5 Principle . 8
6 Interferences and sources of errors . 8
7 Reagents . 8
8 Apparatus . 8
9 Procedure. 10
9.1 Sample pre-treatment . 10
9.2 Blank test . 10
9.3 Method A: Thermal heating under reflux conditions . 10
9.4 Method B: Microwave heating with temperature control at 170 °C – 180 °C . 11
10 Precision data . 12
11 Test report . 13
Annex A (informative) Repeatability and reproducibility data for other matrices . 14
A.1 General . 14
A.2 Interlaboratory studies . 14
A.2.1 Background information in the interlaboratory study for EN 13657 . 14
A.2.2 Background information in the interlaboratory study for EN 16174 . 14
A.2.3 Interlaboratory comparison results . 15
Bibliography . 19

European foreword
This document (CEN/TS 17196:2018) has been prepared by Technical Committee CEN/TC 351
“Construction Products: Assessment of release of dangerous substances”, the secretariat of which is
held by NEN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
A similar standard has been developed for soil, sludge and biowaste, see Annex A.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Introduction
Following an extended evaluation of available methods for content analysis in construction products
(CEN/TR 16045) it was concluded that multi matrix and multi-element digestion methods have
preference over methods developed for single matrices or small groups of matrices. This implies that
for inorganic substances aqua regia digestion is preferred for the digestion of construction products for
content analysis.
This document has been adopted from the work carried out in the context of CEN/TC 292 and
CEN/TC 400 and is very similar to EN 13657 Characterization of waste – Digestion for subsequent
determination of aqua regia soluble portion of elements [1] and EN 16174 Sludge, treated biowaste and
soil – Digestion of aqua regia soluble fractions of elements [2].
This Technical Specification is part of a modular horizontal approach which was adopted in
CEN/TC 351. 'Horizontal' means that the methods can be used for a wide range of materials and
products with certain properties. 'Modular' means that a test standard developed in this approach
concerns a specific step in assessing a property and not the whole chain of measurement (from
sampling to analyses). Beneficial features of this approach are that modules can be replaced by better
ones without jeopardizing the standard chain and duplication of work of in different Technical
Committees for Products can be avoided as far as possible.
The modules that relate to the standards developed in CEN/TC 351 are specified in CEN/TR 16220 [3],
which distinguishes between the modules. This Technical Specification belongs to the analytical step.
The use of modular horizontal standards implies the drawing of test schemes as well. Before executing a
test on a certain construction product to determine certain characteristics it is necessary to draw up a
protocol in which the adequate modules are selected and together form the basis for the entire test
procedure.
WARNING — Persons using this Technical Specification should be familiar with usual laboratory
practice. The reagents used in this Technical Specification are strongly corrosive and partly very
toxic. Safety precautions are absolutely necessary, not only due to the strong corrosive reagents,
but also to high temperature and high pressure.
The use of laboratory-grade microwave equipment with isolated and corrosion resistant safety
devices is required. Domestic (kitchen) type microwave ovens should not be used, as corrosion
by acid vapours may compromise the function of the safety devices and prevent the microwave
magnetron from shutting off when the door is open, which could result in operator exposure to
microwave energy.
All procedures should be performed in a fume hood or in closed force-ventilated equipment. By
the use of strong oxidising reagents, the formation of explosive organic intermediates is
possible, especially when dealing with samples with a high organic content. Do not open
pressurized vessels before they have cooled down. Avoid contact with the chemicals and the
gaseous reaction products.
IMPORTANT — It is absolutely essential that tests conducted according to this Technical
Specification be carried out by suitably trained staff.
1 Scope
This Technical Specification specifies methods for obtaining the aqua regia digestible content of
construction products. Solutions produced by this method are for analysis by inductively coupled
plasma mass spectrometry (ICP-MS) and inductively coupled spectrometry (ICP-OES) for the following
67 elements:
Aluminium (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), bismuth (Bi), boron (B),
cadmium (Cd), calcium (Ca), cerium (Ce), cesium (Cs), chromium (Cr), cobalt (Co), copper (Cu),
dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), gallium (Ga), germanium (Ge), gold
(Au), hafnium (Hf), holmium (Ho), indium (In), iridium (Ir), iron (Fe), lanthanum (La), lead (Pb), lithium
(Li), lutetium (Lu), magnesium (Mg), manganese (Mn), mercury (Hg), molybdenum (Mo), neodymium
(Nd), nickel (Ni), palladium (Pd), phosphorus (P), platinum (Pt), potassium (K), praseodymium (Pr),
rubidium (Rb), rhenium (Re), rhodium (Rh), ruthenium (Ru), samarium (Sm), scandium (Sc), selenium
(Se), silicon (Si), silver (Ag), sodium (Na), strontium (Sr), sulphur (S), tellurium (Te), terbium (Tb),
thallium (Tl), thorium (Th), thulium (Tm), tin (Sn), titanium (Ti), tungsten (W), uranium (U), vanadium
(V), ytterbium (Yb), yttrium (Y), zinc (Zn), and zirconium (Zr).
Solutions produced by the methods are suitable for analysis by cold vapour atomic absorption
or fluorescent spectrometry (CV-AAS, CV-AFS), for mercury (Hg).
The method in this Technical Specification is applicable to construction products.
Digestion with aqua regia will not necessarily accomplish total decomposition of the sample.
The extracted analyte concentrations may not necessarily reflect the total content in the sample.
NOTE Construction products include e.g. mineral-based products (S); bituminous products (B); metals (M);
wood-based products (W); plastics and rubbers (P); sealants and adhesives (A); paints and coatings (C),
see also CEN/TR 16045.
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 15936, Sludge, treated biowaste, soil and waste — Determination of total organic carbon (TOC) by dry
combustion
EN 17087:— , Construction products: Assessment of release of dangerous substances — Preparation of
test portions from the laboratory sample for testing of release and analysis of content
EN ISO 3696:1995, Water for analytical laboratory use — Specification and test methods (ISO 3696:1987)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply
NOTE The terms and definitions, where relevant, were taken from EN 16687:2015.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/

Under preparation. Stage at the time of publication: prEN 17087:2017.
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
analyte
determinand
element, ion or substance to be determined by an analytical method
[SOURCE: EN 16687:2015, 4.1.11]
3.2
aqua regia
digestion solution obtained by mixing one volume of concentrated nitric acid and three volumes of
concentrated hydrochloric acid
3.3
digestion
mineralization of the organic matter of a sample and dissolution of its mineral part (as completely as
possible) when reacted with a reagent mixture
Note 1 to entry: Usually done with a strong, concentrated acid like aqua regia or nitric acid to dissolve inorganic
substances for chemical analysis.
[SOURCE: CEN/TR 16045:2010, 2.2.2]
3.4
digestion vessel
flask where the test portion and the acid solution are mixed together and the digestion is carried out
3.5
digest
solution resulting from acid digestion of a sample
[SOURCE: CEN/TR 16045:2010, 2.2.1]
3.6
dry matter
mass fraction of a sample excluding water expressed as mass fraction calculated by determination of
dry residue or water content
[SOURCE: EN 15934:2012, 3.3]
3.7
microwave unit
microwave digestion system (oven and associated equipment)
3.8
sample
portion of material selected from a larger quantity of material
Note 1 to entry: The manner of selection of the sample should be prescribed in a sampling plan.
Note 2 to entry: The term “sample” is often accompanied by a prefix (e.g. laboratory sample, test sample)
specifying the type of sample and/or the specific step in the sampling process to which the obtained material
relates.
[SOURCE: EN 16687:2015, 3.1.5]
3.9
laboratory sample
sample or sub-sample(s) sent to or received by the laboratory
Note 1 to entry: When the laboratory sample is further prepared by subdividing, cutting, sawing, coring, mixing,
drying, grinding, and curing or by combinations of these operations, the result is the test sample. When no
preparation of the laboratory sample is required, the laboratory sample is the test sample. A test portion is
removed from the test sample for the performance of the test/ analysis or for the preparation of a test specimen.
Note 2 to entry: The laboratory sample is the final sample from the point of view of sample collection but it is
the initial sample from the point of view of the laboratory.
[SOURCE: EN 16687:2015, 3.2.1]
3.10
test sample
analytical sample
sample, prepared from the laboratory sample, from which test portions are removed for testing or for
analysis
[SOURCE: EN 16687:2015, 3.2.2]
3.11
test portion
analytical portion
amount of the test sample taken for testing/ analysis, usually of known weight or volume
EXAMPLE 1 A bag of aggregates is delivered to the laboratory (the laboratory sample). For test
purposes a certain amount of the aggregate is dried, the result is the test sample. Afterwards the column
for a percolation test is filled with a test portion of dried aggregate
EXAMPLE 2 A piece of flooring is delivered to the laboratory (the laboratory sample). For the purpose of
digestion a certain amount is size reduced, the result is the test sample. From the size-reduced test sample a test
portion is taken to execute the digestion. If the digest is to be analysed afterwards e.g. by ICP-MS, the whole
amount of the digest is the laboratory sample again (and without any further treatment also the test sample), the
amount taken for the analytical procedure the test portion.
[SOURCE: EN 16687:2015, 3.2.3]
4 Symbols and abbreviations
For the purposes of this document, the following abbreviations apply.
CAS Chemical Abstracts Service
CASRN CAS Registry Number
CV-AAS Cold vapour atomic absorption spectrometry
CV-AFS Cold vapour atomic fluorescence spectrometry
ICP Inductively coupled plasma
MS Mass spectrometry
OES Optical emission spectrometry
PFA Perfluoroalkoxylalkane
PTFE Polytetrafluoroethene
SRM Standard reference material
5 Principle
A test portion is digested with aqua regia according to one of the following heating procedures:
— Method A: boiling under reflux for 2 h, followed by filtration if necessary and by adjusting
the volume in a volumetric flask;
— Method B: microwave digestion at (175 ± 5) °C for (10 ± 1) min in a closed vessel followed
by filtration if necessary and adjusting the volume in a volumetric flask.
NOTE In the validation testing for other materials (sludge, compost, soil) no significant difference between
the reflux and the microwave method was found. So there seems to be no need to prescribe a particular extraction
method for construction products.
6 Interferences and sources of errors
Due to the volatility of some compounds care shall be taken, that the sample is not heated before
the digestion and that any volatile reaction products formed during the digestion do not escape.
High acid and solute concentrations in the digest may cause interferences at determination.
Contamination shall be avoided. Glass containing e.g. B, Na, K, Al can contaminate samples.
Ensure that all of the test portion is thoroughly mixed with the acid mixture in the digestion vessel.
Some elements of interest can be lost due to precipitation with ions present in the digest solution,
e.g. low soluble chlorides, fluorides and sulfates.
7 Reagents
Use only acids and reagents of recognized analytical grade to avoid high blank values for subsequent
analytical measurements.
7.1 Water, quality 2 according to EN ISO 3696:1995 or better.
7.2 Hydrochloric acid, c(HCl) = 12 mol/l; ρ = 1,18 kg/l.
Other grade may be used provided it is ascertained that the reagent is of sufficient purity to permit
its use without decreasing the accuracy of the subsequent analysis.
7.3 Nitric acid, c(HNO3) = 16 mol/l, ρ = 1,4 kg/l.
7.4 Nitric acid, c(HNO3) = 0,5 mol/l, ρ = 1,0 kg/l.
Dilute 35 ml nitric acid (7.3) to 1 l with water (7.1).
7.5 Antifoaming agent, e.g. n-dodecane (C H ) or Octanol (C H O) are suitable.
12 26 8 18
8 Apparatus
All glassware and plastic ware shall be adequately cleaned and stored in order to avoid any
contamination.
Depending on the concentration of the element of interest, special attention shall be given to the
cleaning of the vessels.
8.1 Apparatus used for Method A
8.1.1 Digestion vessel, temperature- and pressure-resistant and capable of containing the mixture of
sample and digest solution, for example a glass flask of 250 ml. The inner wall of the vessel shall be inert
and shall not release substances to the digest in excess of the purity requirements of the subsequent
analysis.
NOTE 1 Quartz vessels can be used instead of glass vessels.
NOTE 2 It may be necessary to periodically clean the reaction vessels with a suitable surfactant to remove
persistent deposits.
8.1.2 Water cooled reflux condenser adaptable to the digestion vessel (8.1.1). The minimum length
of the condensor is 340 mm, see EN 13657.
8.1.3 Absorption vessel, volatile species trap, in an open digestion system capable of trapping one or
more volatile measurement species, adaptable to the reflux condenser (8.1.2).
8.1.4 Heating device, for example a heating mantle, thermostatic controlled, or an aluminium block
thermostat.
8.2 Apparatus used for Method B
8.2.1 Digestion vessel, for pressurized microwave digestion, preferably of 100 ml volume, reagent-,
temperature- and pressure-resistant and capable of containing the mixture of sample and digest
solution. The vessel shall be suitable for the safe application in the temperature and pressure range
applied, capable of withstanding pressures of at least 3 000 kPa.
Digestion vessels made of PFA, modified PTFE or quartz glass, and equipped with a safety pressure
releasing system to avoid explosion of the vessel, shall be used. The inner wall of the vessel shall be
inert and shall not release contaminations to the digest solution.
NOTE It may be necessary to periodically clean the reaction vessels with a suitable surfactant to remove
persistent deposits.
8.2.2 Microwave digestion system, corrosion resistant and well ventilated. All electronics shall be
protected against corrosion for safe operation.
Use a laboratory-grade microwave oven with temperature feedback control mechanisms.
The microwave digestion system should be able to control the temperature with an accuracy of ± 5 °C
and automatically adjust the microwave field output power within 2 s of sensing. Temperat
...