BS EN ISO 12460-5-2015中文译本180606-200808修订000

BS EN ISO 12460-5-2015
BRITISH STANDARD 英国国家标准
Wood-based panels—Determination of formaldehyde release Part 5:Extraction method (called the perforator method)木基板材—甲醛释放量的测定第五部分：萃取法（也称作穿孔法）
中文翻译版前言
本标准为美国CARB/EPA 认证有关甲醛释放量测试的最新标准要求，与现行中国国家标准要求有一些轻微的变化，现翻译成中文，供CARB/EPA 认证产品的生产控制测试参考之用，所有相关人员应认真研究本标准与中国国家标准的差异，并应用于实际工作中。

考虑到对原版标准理解的准确性，翻译时尽可能采用了直译方式。

文中翻译不妥和错误之处，欢迎指正。

翻译：高连新
校核：张菊
首次翻译稿：2018年6月4日
首次修订：2020年8月8
日
BSI Standards Publication 英国标准学会出版
National foreword（英国）国家前言
This British Standard is the UK implementation of EN ISO12460-5:2015.It supersedes BS EN 120:1992which is withdrawn.
EN ISO12460-5:2015英国国家标准的启用实施，代替已废止的BS EN120:1992。

The UK participation in its preparation was entrusted to Technical Committee B/541,Wood based panels.英国参与其筹备工作的是技术委员会B/541木基板材小组。

A list of organizations represented on this committee can be obtained on request to its secretary.
本委员会所代表的组织名单可在其秘书处获得。

This publication does not purport to include all the necessary provisions of a ers are responsible for its correct application.
这份出版物并没有声称包含了合同的所有必要条款，用户要对其正确的应用负责。

©The British Standards Institution2015.英国标准学会2015
Published by BSI Standards Limited2015英国标准学会2015出版发行
ISBN9780580841408国际标准图书编号
ICS79.060.01国际标准分类代号
Compliance with a British Standard cannot confer immunity from legal obligations.
遵守英国标准不能免除法律义务。

This British Standard was published under the authority of the Standards Policy and Strategy Committee on31December2015.
该英国标准于2015年12月31日在标准政策和战略委员会的授权下发布。

Amendments/corrigenda issued since publication自出版发行以来的修改/勘误表
Date日期Text affected文本的影响ICS79.060.01国际标准分类代号Supersedes EN120:1992代替
English Version英文版
Wood-based panels-Determination of formaldehyde release-Part5:Extraction method(called the perforator method)(ISO 12460-5:2015)
木基板材—甲醛释放量的测定—
第五部分：萃取法（也称作穿孔法）(ISO12460-5:2015)
Panneauxàbase de bois-Détermination du dégagement de formaldéhyde-Partie5:Méthode d'extraction (dite méthode au perforateur)(ISO12460-5:2015) Holzwerkstoffe-Bestimmung der Formaldehyabgabe-Teil5:Extraktionsverfahren(genannt Perforatormethode)(ISO12460-5:2015)
This European Standard was approved by CEN on29August2015.
该欧洲标准于2015年8月29日由CEN（欧洲标准化委员会）批准。

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.
CEN成员一定会遵守CEN/CENELEC(欧洲电工委员会)的内部条例，该条例规定了在没有任何改变的情况下，给予欧洲标准国家标准的地位。

关于这些国家标准的最新清单和参考书目，可向CEN/CENELEC(欧洲电工委员会)管理中心或任何CEN成员申请获得。

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.
这个欧洲标准有三个官方版本（英语、法语、德语），由一名CEN成员负责翻译成其自己的语言，并通知CEN/CENELEC(欧洲电工委员会)管理中心，任何其他语言的版本与官方版本地位相同。

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.
CEN成员是奥地利、比利时、保加利亚、克罗地亚、塞浦路斯、捷克共和国、丹麦、爱沙尼亚、芬兰、前南斯拉夫马其顿共和国、法国、德国、希腊、匈牙利、冰岛、爱尔兰、意大利、拉脱维亚、立陶宛、卢森堡、马耳他、荷兰、挪威、波兰、葡萄牙、罗马尼亚、斯洛伐克、斯洛文尼亚、西班牙、瑞典、瑞士、土耳其和英国的国家标准机构。

European foreword欧洲前言
This document(EN ISO12460-5:2015)has been prepared by Technical Committee ISO/TC89“Woodbased panels”in collaboration with Technical Committee CEN/TC112“Wood-based panels”the secretariat of which is held by DIN.
本文件（EN ISO12460-5:2015）由ISO/TC89技术委员会木基板材分会与CEN/TC112技术委员会木基板材分会合作编制完成，由DIN秘书处组织。

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 June2016,and conflicting national standards shall be withdrawn at the latest by June2016.
该欧洲标准给予国家标准的地位，在2016年6月之前，通过出版相同的文本或通过签注予以确认，最迟在2016年6月，与之冲突的国家标准将被撤销。

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.
请注意，该文件的某些内容可能涉及专利权问题，CEN和/或欧洲电工委员会不负责识别任何或者所有的这些专利权。

This document supersedes EN120:1992.本文件代替EN120:1992 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.
根据CEN欧洲电工委员会的内部规定，下列国家的国家标准化组织一定会实施这个欧洲标准：奥地利、比利时、保加利亚、克罗地亚、塞浦路斯、捷克共和国、丹麦、爱沙尼亚、芬兰、前南斯拉夫马其顿共和国、法国、德国、希腊、匈牙利、冰岛、爱尔兰、意大利、拉脱维亚、立陶宛、卢森堡、马耳他、荷兰、挪威、波兰、葡萄牙、罗马尼亚、斯洛伐克、斯洛文尼亚、西班牙、瑞典、瑞士、
土耳其和英国。

Endorsement notice实施公告
The text of ISO12460-5:2015has been approved by CEN as EN ISO12460-5:2015 without any modification.
ISO12460-5:2015的文本已被CEN批准为EN ISO12460-5:2015，没有任何修改。

BS EN ISO12460-5:2015
ISO12460-5:2015(E) Contents目录Page页码
Foreword前言 (iv)
Introduction简介 (vi)
1Scope范围 (1)
2Normative references引用标准 (1)
3Principle原理 (1)
4Reagents试剂 (1)
5Apparatus仪器装置 (1)
6Test pieces试件 (3)
6.1General概述 (3)
6.2Sampling取样 (3)
6.3Sampling for factory production control工厂生产控制取样 (3)
6.4Sampling for other purposes其它目的取样 (3)
7Procedure程序步骤 (3)
7.1Number of extractions萃取次数 (3)
7.2Determination of moisture content含水率测试 (3)
7.3Extraction in the perforator穿孔萃取 (4)
7.4Blank test空白试验 (4)
7.5Determination of formaldehyde in the extract萃取甲醛的测定 (4)
7.5.1General概述 (4)
7.5.2Principle原理 (5)
7.5.3Reagents试剂 (5)
7.5.4Analytical procedure分析步骤 (5)
7.5.5Calibration curve校准曲线 (5)
7.6Quality assurance品质保证 (6)
8Expression of results结果表示 (7)
8.1Moisture content含水率 (7)
8.2Perforator value穿孔值 (7)
9Test report实验报告 (8)
Annex A(normative)Perforator extraction efficiency test—Calibration of the perforator method附录A(规范性附录)穿孔萃取效率测试—穿孔法的校
准 (13)
Bibliography参考文献 (14)
注：以上目录中的页码为原版页码。

Foreword（ISO）前言
ISO(the International Organization for Standardization)is a worldwide federation of national standards bodies(ISO member bodies).The work of preparing International Standards is normally carried out through ISO technical committees.Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee.International organizations,governmental and non-governmental,in liaison with ISO,also take part in the work.ISO collaborates closely with the International Electrotechnical Commission(IEC)on all matters of electrotechnical standardization.
ISO（国际标准化组织）是一个世界性的国家标准机构联合会（ISO成员机构），制定国际标准的工作通常是通过ISO技术委员会进行的，每个成员对各个技术委员会已经成立的主题感兴趣，都有权在该委员会中派出代表。

国际组织、政府和非政府组织，通过与ISO联系，也参与了这项工作。

ISO与国际电工委员会（IEC）在所有的电工技术标准化问题上密切合作。

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives,Part1.In particular the different approval criteria needed for the different types of ISO documents should be noted.This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part2(see /directives).
用于开发该文件的过程和用于进一步维护的程序在ISO/IEC指令第1部分中描述，尤其应该注意不同类型的ISO文件所需要的不同的审批标准。

该文件是根据ISO/IEC指令的编辑规则第2部分起草的，（见/directives）。

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.ISO shall not be held responsible for identifying any or all such patent rights.Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received(see /patents).
人们注意到，该文件的某些内容可能涉及专利权的问题，ISO不负责识别任何一个或所有这些专利权。

在文件开发过程中确定的任何专利权的细节将列入
（和/或）在ISO的专利声明列表中（见/patents）。

Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.
本文件中使用的任何商标名称都是为方便用户而提供的信息，并不构成认可。

For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,as well as information about ISO’s adherence to the WTO principles in the Technical Barriers to Trade(TBT)see the following URL:Foreword-Supplementary information
关于ISO特定术语和表述与合格评定相关的含义的解释，以及ISO在贸易技术壁垒（TBT）中遵守世贸组织原则的信息，请参阅以下网址：Foreword-Supplementary information（前言-补充信息）
The committee responsible for this document is ISO/TC89,Wood-based panels.
负责本文件的委员会是ISO/TC89，木基板材分会。

This second edition cancels and replaces the first edition(ISO12460-5:2011),which has been technically revised.
第二版取消并取代了第一版（ISO12460-5:2011），这是经过技术修订的。

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.
本次修订的目的是为了提高检测方法的检测极限和对低甲醛释放量板材的再现性。

Compared to ISO12460-5:2011,the following modifications have been made:与ISO12460-5:2011相比，进行了以下修改：
a)in5.3recommendation of cell length for low emitting samples is added;
在5.3，增加了低甲醛释放量时推荐采用的比色皿长度。

b)in6.4relative humidity for conditioning climate is increased to(65±5)%;
在6.4，调节气候的相对湿度增加到（65±5）%。

c)in7.1and8.2procedure and evaluation of third extraction are modified;
在7.1和8.2，对第三次萃取的程序和评价进行了修改。

d)in7.3accuracy of weighing of test pieces enhanced and higher mass of the test pieces
is added as an option for low emitting boards;
在7.3，提高了测试试件的称重准确性，增加了低甲醛释放时选择更大重量的测试试件量。

e)in7.4precision of blank test is improved;
在7.4，进一步完善了空白试验的精密度。

f)in7.5.1fluorimetric determination of formaldehyde is added an option;
在7.5.1，甲醛的分光光度法测定添加了一个选项。

g)in7.5.4temperature of water bath is increased to60°C;
在7.5.4，水浴温度增加到60℃。

h)in8.2modification factors for moisture content is included;
在8.2，包括含水率修正系数。

i)in Figure4calibration curve is modified;
在图4中，修改了标准曲线。

j)Annex A for calibration and quality assurance is added.
在附录A中，增加了校准和品质保证。

ISO12460consists of the following parts,under the general title Wood-based panels—Determination of formaldehyde release:
ISO12460由以下部分组成，木质基板总标题——甲醛释放的测定—Part1:Formaldehyde emission by the1-cubic-metre chamber method
第一部分：1m³气候箱法
—Part3:Gas analysis method
第三部分：气体分析法
—Part4:Desiccator method
第四部分：干燥器法
—Part5:Extraction method(called the perforator method)
第五部分：萃取法（也称为穿孔法）
Additional parts dealing with small-scale chamber method is planned.
另外还计划编制小气候箱法的其他部分。

Introduction简介
The“perforator value”as determined by the method laid down in this part of ISO12460 is considered to be the“formaldehyde content”of the tested board.
由ISO12460的这部分标准内容所规定的方法测定的“穿孔值”被认为是测试板材的“甲醛含量”。

The test results are dependent on the specific board conditions at the time of testing.
测试结果取决于测试时板材的特性。

The emission of formaldehyde from wood-based panels(e.g.particleboard,plywood, fibreboard,OSB)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.
来自木基板材（如刨花板、胶合板、纤维板、OSB）的甲醛释放是一个复杂的过程，对于一个给定的板材，测试结果取决于测试时的使用年限、老化条件、含水率等。

In addition,the correlation between the perforator value and the formaldehyde emission of the board depends on the type of board.
另外，穿孔值与板的甲醛释放量之间的相关性取决于板材的类型。

Wood-based panels—Determination of formaldehyde release—Part5:Extraction method(called the perforator method)
木基板材—甲醛释放量的测定第五部分：萃取法（也称作穿孔法）
1Scope范围
This part of ISO12460specifies 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.
ISO12460的这一部分规定了一种称为穿孔法的萃取操作方法，用于测定非层压板材和未经涂饰饰面处理的木基板材的甲醛释放量。

2Normative references引用标准
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.
下列文件全部或部分地在本文件中被规范地引用，对于其应用来说是必不可少的。

凡是标注日期的引用文件，仅注日期的版本适用于本文件。

对于未注明日期的引用文件，其最新版本（包括所有的修改单）适用于本文件。

ISO16979,Wood-based panels—Determination of moisture content
ISO16979，木基板材-含水率测定
ISO16999,Wood-based panels—Sampling and cutting of test pieces
ISO16999，木基板材-取样和试件切割制备
3Principle原理
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.
试件中的甲醛被沸腾的甲苯萃取出来，然后转移到蒸馏水或者软化水中，水溶液中的甲醛含量通过乙酰丙酮分光光度法测定。

4Reagents试剂
For the analysis,only reagents of analytical quality and distilled or demineralized water shall be used.
在分析实验中，只可使用分析纯质量的试剂和蒸馏水或者脱盐软化水。

4.1Toluene,which is free from water and from impurities which may interfere with the test.甲苯，不含水和其它干扰测试的杂质
4.2Acetylacetone,of analytical grade.乙酰丙酮，分析纯
4.3Ammonium acetate,of analytical grade.醋酸铵，分析纯
4.4Formaldehyde solution.甲醛溶液Commercially available formaldehyde solution(concentration typically between35% mass fraction to40%mass fraction).市购甲醛溶液（浓度为质量分数35%～40%）5Apparatus仪器装置
5.1Precision balance,with0,01g scale intervals.精密天平，分度值0.01g
5.2Well-ventilated oven,capable of maintaining a temperature of(103±2)°C.
鼓风干燥箱，温度可保持（103±2）℃
5.3Spectrophotometer,capable of measuring absorbance at412nm.A cell of50mm path length is recommended,especially for low emitting samples.
分光光度计，可以在波长412nm处测量吸光度，推荐使用光程为50mm的比色皿，尤其是低甲醛释放量的样品。

5.4Extraction apparatus.穿孔萃取仪
The apparatus consists of the following:仪器由以下部分组成：—spiral condenser(Dimroth cooler),total length:approximately400mm,cone45/40, socket29/32(item reference2);
—螺旋式冷凝器（蛇形管冷凝器），总长度大约400mm，圆锥形大小接头45/40，圆锥形磨口配合29/32（参考项目2）
—conical adaptor,socket45/40,cone71/51(item reference3);
—圆锥形大小接头，磨口配合45/40，圆锥形大小接头71/51（参考项目3）—filter insert,porosity P160(100pm to160pm),bowl and filter diameters:60mm (item reference4);
—穿孔器，孔隙率为P160（100pm～160pm）（参考项目4）—perforator attachment,1000ml,with stopcock(4mm bore),socket71/51,cone 29/32(item reference5);
—穿孔器附件，1000ml，具有活塞开关（4mm孔径），磨口配合71/51，锥形大小接头29/32（参考项目5）
—conical adaptor,socket29/32,cone45/40(item reference8);
—圆锥形大小接头，磨口配合29/32，锥形大小接头45/40（参考项目8）—1000ml round bottom flask,socket45/40(item reference9);
—1000ml圆底烧瓶，磨口配合45/40（参考项目9）—(double)bulbed tube,cone29/32(length:approximately380mm),external diameter: approximately10mm,bulb diameter:approximately50mm,distance between bulb and bottom end of tube:approximately200mm(distance between the bulbs:approximately 50mm)(item reference6);
—（双）球形管，锥形大小接头29/32（长度大约380mm），外径大约10mm，球直径大约50mm，球距离管子底部的距离大约200mm（两球之间的距离大约50mm）（参考项目6）
—absorption bulb(e.g.conical flask250ml)(item reference7);
—吸收甁（如250ml锥形瓶）（参考项目7）
—heating mantle(item reference10).
—加热套（参考项目10）
The item references are given in Figure1.Details of the apparatus are shown in Figure2 and Figure3.Permanent PTFE seals should be used rather than paraffin or silicone grease sealants.
在图1中给出了参考项目，该设备的详细信息如图2和图3所示，应该使用永久性的聚四氟乙烯密封剂，而不是石蜡或硅脂密封剂。

5.5Laboratory equipment实验室仪器
The apparatus consists of the following:包括以下仪器装置：—volumetric flask,2000ml,calibrated at20°C;
—容量瓶，2000ml，在20℃校准刻度
—conical flask,250ml;锥形瓶，250ml —precision burette,50ml,calibrated at20°C;精密滴定管，50ml，在20℃校准—watch glass,with diameter of about120mm;玻璃表面皿，直径大约120mm —two volumetric flasks,1000ml,calibrated at20°C;
—两个容量瓶，1000ml，在20℃校准
—six volumetric flasks,100ml,calibrated at20°C;
—6个容量瓶，100ml，在20℃校准—volumetric pipette,100ml,calibrated at20°C;移液管，100ml，在20℃校准—volumetric pipette,25ml,calibrated at20°C;移液管，25ml，在20℃校准—volumetric pipettes(calibrated at20°C),1ml,2ml,5ml,10ml,15ml,20ml,25ml, 50ml,100ml;
—移液管（在20℃校准），1ml，2ml，5ml，10ml，15ml，20ml，25ml，50ml，100ml
—three volumetric pipettes,10ml,calibrated at20°C;
—3支移液管，10ml，在20℃校准—stoppered flasks,each50ml;具塞烧瓶，每个50ml
—two volumetric cylinders,250ml;两个量筒，250ml
—water bath,capable of maintaining a temperature of(60±1)°C;
—水浴，可维持温度在(60±1)°C
—water bath,capable of maintaining a temperature in the range of20°C to25°C;—水浴，可维持温度范围在20℃～25℃—desiccator.干燥器
6Test pieces试件
6.1General概述
Sampling and cutting are done in accordance with ISO16999.
取样和切割操作按照ISO16999执行。

6.2Sampling取样
6.2.1The test pieces are to be taken and evenly distributed over the width of the(cooled) board,but excluding a250mm wide strip from the end of each board.
测试试件的制取，要在（已冷却的）板的宽度方向上均匀分布，但要去除每个板边250毫米宽度的地方。

6.2.2Take12test pieces of25mm×25mm×thickness of the board for the determination of the moisture content and a sufficient number of test pieces of the same dimensions to obtain approximately500g of the board for the extraction by perforator.
取12块25mm×25mm×厚度的试件，用于测定含水率，并取足够数量的相同尺寸的试件，以获得大约500g的试件板，用于穿孔萃取。

6.3Sampling for factory production control工厂生产控制取样
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.
如果该方法用于生产控制，则选择在板冷却后立即进行取样切割，从板材上切割取下的试件应在室温下密封储存。

The formaldehyde determination should be carried out not more than72h after sampling.应在制样后72h内进行甲醛测定。

6.4Sampling for other purposes其它目的取样
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.
如果本方法用于其它目的，例如，已安装好的板，采用的取样、试件制备和
平衡处理等所有影响最终结果的方法，都需经双方当事人同意，并在试验报告中说明。

Unless otherwise agreed,the test pieces shall be conditioned to constant mass at a temperature of(20±2)°C and a relative humidity of(65±5)%.
除非另有协议，试件应在温度（20±2）℃，相对湿度（65±5）%的条件下处理至质量恒定。

Constant mass is considered to have been reached when the results of two successive weighings carried out at intervals of not less than24h do not differ by more than0,1% of the mass of the test pieces.
相隔至少24h，两次连续称重结果之差不超过试件质量的0.1%，即视为质量恒定。

Contamination of test pieces from other sources of formaldehyde during conditioning shall be avoided.
在平衡处理期间，应避免其它来源的甲醛污染试件。

7Procedure程序步骤
7.1Number of extractions萃取次数
The extractions are to be carried out in duplicate.
试样一式两份进行两次萃取试验。

For factory production control,a single extraction can be sufficient.
用于工厂生产控制时，只需一次萃取就够了。

The individual values of a duplicate extraction shall not deviate by more than0,5 mg/100g,otherwise,a third extraction has to be carried out.
两次重复萃取试验的穿孔值之差不得超过0.5mg/100g，否则，必须进行第三次萃取试验。

7.2Determination of moisture content含水率测定Determine the moisture content in accordance with ISO16979.
含水率测定按照ISO16979执行。

Determine the moisture content in duplicate on a sample of at least four test pieces(25 mm×25mm)with a minimum mass of20g.
含水率测定试件一式两份，每份试件至少4块（25mm×25mm），质量最少为20g。

Weigh the sample(5.1)to an accuracy of0,1g onto the watch glass(5.5)and dry in the oven(5.2)at a temperature of(103±2)°C to constant mass(about12h).
用玻璃表面皿（5.5）在精度为0.1g的天平上称量样品（5.1），在烘箱中（5.2）温度（103±2）℃干燥到恒定质量（大约12h）。

Constant mass is considered to have been reached when the results of two successive weightings carried out at intervals of not less than6h do not differ by more than0,1% of the mass of the test pieces.
在不小于6h的间隔内，当两次连续称重的结果不超过试件质量的0.1%，即视为质量恒定。

After the removal from the drying oven,the test pieces shall be allowed to cool in a desiccator before weighing.
从干燥箱中取出试件后，在称重前，应将试件置于干燥器中冷却。

7.3Extraction in the perforator穿孔萃取
Before the apparatus is used,the sidearm of the perforator attachment shall be provided with thermal insulation in order to achieve circulation of the toluene.
在使用该装置之前，应对穿孔器附件边管进行保温处理，以利于甲苯回流。

About110g of test pieces are weighed to0,1g and put into the round bottom flask(5.4). 600ml of toluene(4.1)are added.About1000ml of distilled water is poured into the perforator attachment leaving a space of20mm to30mm between the surface of the water and the siphon outlet.Subsequently,the round bottom flask is connected to the perforator.The condenser and the gas absorption equipment are then connected.The absorption bulb of the gas absorption equipment(5.4)is filled with about100ml of distilled water and connected to the apparatus.
称重大约110g试件，精确到0.1g，放入圆底烧瓶（5.4），加入600ml甲苯（4.1），注入大约1000ml蒸馏水到穿孔器附件中，使液面距离虹吸管出口20～30mm。

随后，连接穿孔器与圆底烧瓶，再连接冷凝器和气体吸收装置，在气体吸收装置（5.4）的吸收瓶内加入大约100毫升的蒸馏水，并连接到设备上。

For boards with low formaldehyde content,the mass of the test pieces can be extended up to200g provided that the density of the samples enables such an extension.
低甲醛含量的板材，如果样品的密度允许，试件的质量可以增加到200g。

When the apparatus has been assembled,the cooling water and heating are turned on. Toluene shall flow back regularly throughout the whole period of perforation with a reflux rate of70drops to90drops per minute.
仪器装置组装完毕后，打开冷却水，并加热。

在整个穿孔期间，甲苯应有规律地回流，回流速度为每分钟70滴～90滴。

Care shall be taken that no water flows back from the absorption bulb(item reference7) into other parts of the equipment during and after the extraction process.
应注意，在萃取过程中和萃取完之后，要防止吸收瓶（项目参考7）中的水虹吸回到仪器装置的其他部位。

The extraction is carried out for(120±5)min starting at the moment that the first bubbles pass through the filter insert.The heating shall be such that the onset of bubbling occurs between20min and30min after turning on the heating device.
调节加热器，开启加热装置后，加热20分钟至30分钟后开始有气泡产生，从通过穿孔器的第一个连续气泡群开始计时，整个萃取过程持续进行（120±5）min。

After these120min,the heating is switched off and the gas absorption bulb removed.
120分钟后，关闭加热开关，移开气体吸收瓶。

The water contained in the perforator is,after cooling to room temperature,transferred into the volumetric flask by means of the stopcock.The perforator is rinsed twice,each time with200ml of distilled water.The rinsing water is poured into the volumetric flask and the toluene discarded.The water contained in the absorption bulb of the gas absorption equipment is poured into the flask.The volume of the water contained in the flask is then made up to2000ml with distilled water.
穿孔器内的水在冷却至室温后，通过活塞开关转移到容积瓶中，冲洗穿孔器两次，每次使用200ml蒸馏水，将冲洗水合并转移到容量瓶中，并清除甲苯，气体吸收装置吸收瓶中的水转移到容量瓶中，然后将容量瓶用蒸馏水补足定容至
2000ml。

7.4Blank test空白试验
When using toluene from a new batch,carry out an extraction without test pieces applying the procedure as in7.3.
当使用新批次的甲苯时，按照7.3的步骤，不加试件进行萃取操作。

The quality of toluene is checked by this test.lf the blank value of formaldehyde is higher than0,2mg/600ml of toluene,the toluene shall be rejected.
该试验用于复核甲苯的质量，如果甲醛的空白实验值高于0.2mg/600ml甲苯，则该甲苯不能使用。

7.5Determination of formaldehyde in the extract萃取甲醛的测定
7.5.1General概述
The formaldehyde content of the aqueous extract is determined photometrically using the acetylacetone method.
萃取物中甲醛含量的测定采用乙酰丙酮显色的分光光度法。

A fluorimetric determination may be used optionally.
可以选择性地使用荧光测定法。

7.5.2Principle原理
The determination is based on the Hantzsch reaction in which aqueous formaldehyde reacts with ammonium ions and acetylacetone to yield diacetyldihydrolutidine(DDL). DDL has an absorbance maximum at412nm.The reaction is highly specific to formaldehyde.
该测定方法是基于Hantzsch（汉奇）反应，在此反应中，甲醛水溶液与铵离子和乙酰丙酮发生反应，生成二乙酰基二氢卢剔啶（DDL）。

DDL的最大吸光率为412nm，此反应对甲醛高度灵敏。

Other suitable photometric procedures can also be used.
还可以使用其他适当的光度法。

7.5.3Reagents试剂
7.5.3.1Acetylacetone solution乙酰丙酮溶液
4ml acetylacetone is transferred to a1000ml volumetric flask,dissolved in distilled water,and filled to volume with distilled water.
移取4ml乙酰丙酮，用蒸馏水溶解，加入到1000ml容量瓶中，用蒸馏水定容至刻度。

7.5.3.2Ammonium acetate solution醋酸铵溶液
200g ammonium acetate is transferred to a1000ml volumetric flask,dissolved in distilled water,and filled to volume with distilled water.
称取200g醋酸铵，用蒸馏水溶解，转移到1000ml容量瓶中，用蒸馏水定容至刻度。

Optionally,a premixed reagent of acetylacetone and ammonium acetate as described in ISO12460-4:2008,4.1can be used.
根据需要，可以按照ISO12460-4:2008-4.1所描述的方法，使用乙酰丙酮和醋酸铵的预混合试剂。

7.5.4Analytical procedure分析步骤
10ml is taken from the aqueous solution(7.3)with a pipette and added to10ml acetylacetone solution(7.5.3.1)and10ml ammonium acetate solution(7.5.3.2)in a50 ml flask.The flask is stoppered,shaken,and warmed for10min in a water bath of60°C. The heated flask is then cooled in a water bath operated in a temperature range between 20°C and25°C for at least15min protected from sunlight or is cooled to room temperature,protected against the influence of light(for about1h).The absorbance of this solution is determined at a wavelength of412nm against distilled water using a spectrophotometer(5.3).A blank value is determined in parallel with distilled water and taken into consideration in the determination of the perforator value(8.2).
用移液管从水溶液（7.3）中取出10ml，并在一个50ml的带塞三角烧瓶中加入10ml乙酰丙酮溶液（7.5.3.1）和10ml醋酸铵溶液（7.5.3.2），摇匀，在60℃水浴中加热10分钟，然后，将热的烧瓶放置在温度在20℃～25℃的避光处水浴中冷却至少15分钟，或者在避光处存放冷却到室温（大约1h）。

用分光光度计（5.3）测定溶液的吸光度，采用波长为412纳米，以蒸馏水作为对比溶
液，调零。

用蒸馏水平行测定空白值，并在穿孔值的测定（8.2）中考虑。

※张菊注：以前、包括现在我们的做法是把混合液放在60℃水浴中加热10分钟，然后避光冷却1小时再比色。

新标准现在提出了两种方法：一种就是60℃水浴中加热10分钟，然后避光冷却1小时再比色；另一种是在60℃水浴中加热10分钟，然后放在温度在20℃～25℃的水浴中避光冷却至少15分钟再比色。

When smaller volumes of solutions with the same ratio of reagents are used,e.g.
applying digital/automatic pipettes,it should be ensured that enough analytical solution is available for the spectophotometric determination.Furthermore it should be taken into consideration that measurement errors could have increasing influence on the result.当使用体积更小的相同比例的试剂时，例如，应用数字/自动吸管时，应确
保有足够的分析溶液来进行分光光度法测定。

此外，还应考虑到测量误差可能对结果有越来越大的影响。

7.5.5Calibration curve校准曲线
7.5.5.1General概述
The calibration curve(see Figure4)is produced from a standard formaldehyde solution, the concentration of which has been determined by iodometric titration.The calibration curve shall be checked at least once a week.It is possible to modify this frequency if it is proved that the slope of the standard curve does not deviate.In this case,the checking shall be made at least once a month and for each change of reagents.
校准曲线（见图4）是通过标准甲醛溶液绘制的，甲醛的浓度由碘量法测定，校准曲线每周至少检查一次，如果证明了标准曲线的斜率没有发生偏离，就可以修改这个检查频率，在这种情况下，每个月至少要检查一次，每次更换试剂时也要检查。

7.5.5.2Formaldehyde standard solution甲醛标准溶液Reagents:试剂
—Standard iodine solution c(I2)=0,05mol/l碘标准溶液—Standard sodium thiosulfate solution c(Na2S2O3)=0,1mol/l硫代硫酸钠标准溶液—Standard sodium hydroxide solution c(NaOH)=1mol/l氢氧化钠标准溶液
—Standard sulphuric acid solution c(H2SO4)=1mol/l硫酸标准溶液—Starch solution=1%淀粉溶液The solutions shall be standardized before use.这些溶液在使用前应标定。

About2,5g formaldehyde solution(concentration35%to40%)are diluted in a1000 ml volumetric flask with distilled water and made up to the mark.The exact formaldehyde concentration is determined as follows.
取大约2.5g甲醛溶液（浓度35%～40%），移入1000ml容量瓶中，用蒸馏水稀释至刻度，精确的甲醛浓度铵以下方法标定：
20ml of the formaldehyde standard solution are mixed with25ml iodine solution and 10ml sodium hydroxide solution.After15min standing protected from light,15ml of sulfuric acid solution are added to the mixture.The excess iodine is back-titrated with the thiosulfate solution.At the end of the titration,some drops of starch solution are added as an indicator.A blank test with20ml distilled water is carried out in parallel.
20毫升的甲醛标准溶液与25ml碘溶液和10ml氢氧化钠溶液混合在一起，避光静置存放15分钟，将15毫升硫酸溶液添加到该混合物中，过量的碘用硫代硫酸钠溶液滴定，在滴定接近终点时，加入数滴淀粉溶液作为指示剂，用20ml 蒸馏水做平行空白试验。

The formaldehyde content is calculated by using Formula(1):
甲醛含量按公式（1）计算：
c(HCHO)=(V0-V)×15×c(Na
2S
2
O
3
)×1000/20 (1)
where式中：
c(HCHO)is the formaldehyde concentration,in milligrams per litre(mg/I);
甲醛浓度，单位为毫克每升（mg/L）
c(Na2S2O3)is the concentration of the thiosulfate solution,in mols per litre(mol/l);
硫代硫酸盐溶液的浓度，单位为摩尔每升（mol/L）
V0is the volume of thiosulfate solution for the blank test,in millilitres(ml);
空白试验消耗硫代硫酸盐溶液的体积，单位为毫升（ml）
V is the volume of thiosulfate titration solution for the test,in millilitres(ml).
测定甲醛实验消耗硫代硫酸盐溶液的体积，单位为毫升（ml）。