prEN 120 rev
(Main)Wood-based panels - Determination of formaldehyde release - Extraction method (called the perforator method)
Wood-based panels - Determination of formaldehyde release - Extraction method (called the perforator method)
This document describes an extraction method called the perforator method, to determine the formaldehyde content of unlaminated and uncoated wood-based panels.
Holzwerkstoffe - Bestimmung des Formaldehydgehaltes - Extraktions-verfahren (genannt Perforatormethode)
Diese Europäische Norm legt ein Extraktionsverfahren, bekannt als "Perforatormethode" fest. Sie wird angewendet für die Bestimmung des Formaldehydgehaltes von unbeschichteten und unlackierten Holzwerkstoffen.
Panneaux à base de bois - Détermination du dégagement de formaldéhyde - Méthode d'extraction (dite méthode au perforateur)
La présente Norme européenne prescrit une méthode d'extraction dite « méthode au perforateur ». Elle est utilisée pour la détermination de la teneur en formaldéhyde des panneaux à base de bois non mélaminés et non revêtus d’une finition.
Lesne plošče - Določevanje prostega formaldehida - Ekstrakcijska metoda (imenovana perforatorska metoda)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-januar-2012
/HVQHSORãþH'RORþHYDQMHSURVWHJDIRUPDOGHKLGD(NVWUDNFLMVNDPHWRGD
LPHQRYDQDSHUIRUDWRUVNDPHWRGD
Wood-based panels - Determination of formaldehyde release - Extraction method (called
the perforator method)
Holzwerkstoffe - Bestimmung des Formaldehydgehaltes - Extraktions-verfahren (genannt
Perforatormethode)
Panneaux à base de bois - Détermination du dégagement de formaldéhyde - Méthode
d'extraction (dite méthode au perforateur)
Ta slovenski standard je istoveten z: prEN 120 rev
ICS:
79.060.01 /HVQHSORãþHQDVSORãQR Wood-based panels in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
DRAFT
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2011
ICS 79.060.01 Will supersede EN 120:1992
English Version
Wood-based panels - Determination of formaldehyde release -
Extraction method (called the perforator method)
Panneaux à base de bois - Détermination du dégagement Holzwerkstoffe - Bestimmung des Formaldehydgehaltes -
de formaldéhyde - Méthode d'extraction (dite méthode au Extraktions-verfahren (genannt Perforatormethode)
perforateur)
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 112.
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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland 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
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 120 rev:2011: E
worldwide for CEN national Members.
prEN 120:2011 (E)
Contents Page
Foreword .3
Introduction .4
1 Scope .4
2 Normative references .4
3 Principle .4
4 Reagents .4
5 Apparatus .5
6 Test pieces .6
6.1 General .6
6.2 Sampling .6
6.3 For production control .6
6.4 For other purposes .6
7 Procedure .6
7.1 Number of extractions .6
7.2 Determination of moisture content .7
7.3 Extraction in the perforator .7
7.4 Blank test .7
7.5 Determination of formaldehyde in the extract .8
7.5.1 General .8
7.5.2 Principle .8
7.5.3 Reagents .8
7.5.4 Analytical Procedure .8
7.5.5 Calibration curve.8
7.6 Quality assurance .9
8 Expression of results .9
8.1 Moisture content .9
8.2 Perforator value . 10
9 Test report . 11
Annex A (normative) Perforator extraction efficiency test – Calibration of the perforator method . 16
Bibliography . 17
prEN 120:2011 (E)
Foreword
This document (prEN 120:2011) has been prepared by Technical Committee CEN/TC 112 “Wood-based
panels”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 120:1992.
The objective of the revision was to improve the detection limit and the reproducibility of the
method with regard to boards with low formaldehyde content.
Compared to EN 120:1992 the following modifications have been made:
a) in 5.3 recommendation of cell length for low emitting samples added;
b) in 6.4 relative humidity for conditioning climate increased to (50 ± 5) %;
c) in 7.1 and 8.2 procedure and evaluation of third extraction modified;
d) in 7.3 accuracy of weighing of test pieces enhanced and higher mass of the test pieces added as an
option for low emitting boards;
e) in 7.4 precision of blank test improved;
f) in 7.5.1 fluorimetric determination of formaldehyde added an option;
g) in 7.5.4 temperature of water bath increased to 60 °C;
h) in 8.2 modification factors for moisture content included;
i) in Figure 4 calibration curve modified;
j) Annex A for calibration and quality assurance added.
prEN 120:2011 (E)
Introduction
The 'perforator value' as determined by the method laid down in this standard is considered to be the
‘formaldehyde content' of the tested board.
The test results shall be considered in relation to the specific board conditions at the time of testing.
The emission of formaldehyde from wood-based panels (e.g. particleboard, plywood, fibreboard) is a complex
process. For a given board, the test result depends upon the age, ageing conditions, moisture content, etc. at
the time of testing.
In addition, the correlation between the Perforator value and the formaldehyde emission of the board depends
on the type of board.
1 Scope
This European Standard specifies an extraction method, known as the 'Perforator method'. It is used for the
determination of the formaldehyde content of unlaminated and uncoated wood-based panels.
2 Normative references
The following referenced documents are indispensable for the application 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 322, Wood-based panels ― Determination of moisture content
EN 326-1, Wood-based panels ― Sampling and cutting of test pieces
3 Principle
The formaldehyde is extracted from test pieces by means of boiling toluene and then transferred into distilled
or demineralized water. The formaldehyde content of this aqueous solution is determined photometrically by
the acetylacetone method.
4 Reagents
For the analysis, only reagents of analytical quality and distilled or demineralized water shall be used.
4.1 Toluene, which is free from water and from impurities which may interfere with the test.
4.2 Acetylacetone, of analytical grade.
4.3 Ammonium acetate, of analytical grade.
4.4 Formaldehyde solution
Commercially available formaldehyde solution (concentration typically between 35 to 40 %).
NOTE Commercially prepared solutions may be used, provided it can be shown that they give an equivalent result.
prEN 120:2011 (E)
5 Apparatus
5.1 Precision balance, with 0,001 g scale intervals.
5.2 Well-ventilated oven, capable of maintaining a temperature of (103 ± 2) °C.
5.3 Spectrophotometer, capable of measuring absorbance at 412 nm. A cell of 50 mm path length is
recommended, especially for low emitting samples.
5.4 Extraction apparatus
The apparatus consists of:
spiral condenser, total length: approximately 400 mm, cone 45/40; socket 29/32 (item reference 2);
conical adaptor, socket 45/40, cone 71/51 (item reference 3);
filter insert, porosity P 160 (100 pm to 160 pm), bowl and filter diameters: 60 mm (item reference 4);
perforator attachment, 1000 ml, with stopcock (4 mm bore), socket 71/51, cone 29/32 (item reference 5);
conical adaptor, socket 29/32, cone 45/40 (item reference 8);
1000 ml round bottom flask, socket 45/40 (item reference 9);
(double) bulbed tube, cone 29/32 (length: approximately 380 mm), external diameter: approximately
10 mm, bulb diameter: approximately 50 mm, distance between bulb and bottom end of tube:
approximately 200 mm (distance between the bulbs approximately 50 mm) (item reference 6):
absorption bulb (e.g. conical flask 250 ml) (item reference 7).
NOTE 1 The item references are given in Figure 1.
NOTE 2 Permanent PTFE seals should be used rather than paraffin or silicone grease sealants.
5.5 Laboratory equipment
Volumetric flask, 2000 ml, calibrated at 20 °C;
Conical flask, 250 ml;
Precision burette, 50 ml, calibrated at 20 °C;
Watch glass, with diameter of about 120 mm;
Two volumetric flasks, 1000 ml, calibrated at 20 °C;
Six volumetric flasks, 100 ml, calibrated at 20 °C;
Volumetric pipette or automatical/digital pipette, 100 ml, calibrated at 20 °C;
Volumetric pipette or automatical/digital pipette, 25 ml, calibrated at 20 °C;
Volumetric pipettes (calibrated at 20 °C), 1 ml, 2 ml, 5 ml, 10 ml, 15 ml, 20 ml, 25 ml, 50 ml, 100 ml;
Three volumetric pipettes or automatical/digital pipettes, 10 ml, calibrated at 20 °C;
prEN 120:2011 (E)
Stoppered flasks, each 50 ml;
Two volumetric cylinders, 250 ml;
Water bath;
Desiccator.
6 Test pieces
6.1 General
Sampling and cutting are done in accordance with EN 326-1.
6.2 Sampling
6.2.1 The test pieces are to be taken, evenly distributed, over the width of the (cooled) board, but excluding
a 500 mm wide strip at either end of the board.
6.2.2 Take 12 test pieces of 25 mm x 25 mm x thickness of the board for the determination of the moisture
content and a sufficient number of test pieces of the same dimensions to obtain approximately 500 g of the
board for the extraction by perforator.
6.3 For production control
If this method is used for production control, the board selected for sampling is immediately cut up after
cooling. The test pieces taken from the board are to be stored hermetically sealed at room temperature.
The formaldehyde determination should be carried out not more than 72 h after sampling.
6.4 For other purposes
If this method is used for other purposes, e.g. for boards already installed, the method chosen for sampling,
preparation of test pieces and conditioning, all which influence the final result, shall be agreed between the
parties and indicated in the test report.
Unless otherwise agreed, the test pieces shall be conditioned to constant mass at a temperature of
(23 ± 1) °C and a relative humidity of (5
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.