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IntroductionRegulatory requirements relating to constructionproducts and the indoor environment are currentlyundergoing major review in many parts of the world. Keyexamples are:

• European Commission (EC) mandate M/366 of theConstruction Product Directive (CPD) and the newEC Construction Products Regulation (CPR)

• US International Green Construction Code (IgCC)• European and Chinese regulations on hazardous

chemicals (‘REACH’)• 2009 French law describing the labelling of

construction and decorative productsWith the population of the EU now exceeding 500 million,the impending implementation of the EC CPR will havearguably the biggest impact on construction anddecorative product trades around the world. Whenfinalised, the CPR will require manufacturers to carry outchemical emissions testing as part of the CE markingprocess. Both product certification by an accredited thirdparty laboratory and routine, in-house ‘factory productioncontrol’ of emissions are expected to be required. Reference methods for emissions testing are specifiedfor product certification. They are designed to simulatereal-world use of the product after installation in abuilding and are, by definition, time-consuming (3–28days) and expensive to run. To complement referencemethods, quicker, simpler emissions screening tests havebeen introduced for routine industrial applications. Newtechnologies/procedures allow chemical emissionsscreening to be readily implemented in a routine factoryproduction (quality) control environment. This will reducethe test burden on industry and aid the development oflow-emission, higher-value products.

With innovations such as the Micro-Chamber/ThermalExtractor™ (µ-CTE™) for fast emissions screening andTargetView™ for automatic interpretation of complex gaschromatography/mass spectrometry (GC/MS) data,Markes International has been at the forefront of effortsto simplify material emissions testing for manufacturers.This Markes publication summarises recent regulatorychanges, the likely impact on industry, and ongoingtechnical developments to minimise the burden andmaximise the opportunity for affected trades.

Changes in the regulatory landscapeSince 1989, Essential Requirement (ER) 3 of the ECConstruction Products Directive has stated that chemicalemissions from products used indoors must notadversely affect the indoor environment or the healthand comfort of building occupants. A wide range ofstructural and decorative materials are covered by thislegislation; however ER3 was not properly implementedfor many years, largely due to the lack of suitable andbroadly applicable (‘horizontal’) test methods. Current legislative activity is rectifying this situation; in2005, EC mandate M/366 was adopted under the CPDand required the European standards organisation (CEN)to finalise and validate methods for testing chemicalemissions. A new CEN Technical Committee (TC 351) wasset up to complete the task, with the aim of makingchemical emissions testing a mandatory part of CEmarking for construction products across Europe. Thisprocess is now well underway and has been reinforced bythe promulgation of new German and French nationalregulations, which require emissions testing andestablish performance criteria for product approval orclassification.In parallel with the ongoing work of CEN TC 351,European legislators have been developing areplacement to the 1989 Directive. The new Construction

TDTSThermal Desorption Technical Support

Note 68: Using Markes emission screening technology tosimplify compliance with the latest construction product

regulationsKeywords

Construction Products Regulation, Construction Products Directive, EC Mandate M/366

www.markes.com

Markes International Ltd. T: +44 (0) 1443 230935 F: +44 (0) 1443 231531 E: [email protected]

Products Regulation (CPR) is currently progressingthrough the final stages of debate in the EuropeanParliament and is expected to be adopted by the end of2010, with implementation by 2012. ‘Regulations’ differfrom ‘Directives’ in Brussels’ terminology in that theyenter European law immediately; i.e. without memberstates having to pass their own national regulation. The EC REACH (‘registration, evaluation, authorisationand restriction of chemical substances’) directive,relating to chemicals and their safe use, was adopted bythe European Parliament and came into force in June2007. Similar legislation is currently being implementedin China. Under REACH, chemical manufacturers,importers and downstream users will need to preparetechnical dossiers and/or ‘Chemical Safety Reports’depending on tonnages. If a consumer product containsa potentially hazardous chemical at a level above 0.1%,and if it is possible for that chemical to be emitted undernormal usage conditions (intentional or unintentionalrelease), this must be assessed. Current guidance onimplementation of emission testing for articles andpreparations (general consumer goods) under EuropeanREACH specifies many of the methods developed forconstruction products 1.Concern relating to product emissions and their potentialimpact on indoor environments and human health aredriving similar regulatory developments in the US. Aconsortium of American agencies including the nationalstandards agency ANSI and the indoor air quality interestgroup ASHRAE have recently produced Standard 189.1(2009) ‘Standard for the design of high-performancegreen buildings’. In parallel with this, another US agency,the International Code Council, is collaborating withASTM and the American Institute of Architects toincorporate mandatory emissions testing into US buildingcodes for public building projects. This ‘InternationalGreen Construction Code’ (IgCC) initiative is expected tobe fully implemented and enforced by 2012.

Which industrial sectors (trades) will beaffected?Amendments to construction product regulations impacta surprising number of trades, including those involved inthe manufacture of thermal insulating materials, wood-based products, plasterboard, paints and varnishes,adhesives, sealants for joints, flooring materials,structural foam and wall coverings.In the long term, REACH-type regulations around theworld are expected to expand the requirement to monitorchemical emissions away from just constructionmaterials, to include a wide range of consumer productsused indoors. Theoretically, over 70% of manufacturingindustry could be impacted.

What do reference methods for materialsemissions testing involve?Standard reference methods for testing productemissions to indoor air involve placing a representativesample of the material into a large test chamber tosimulate real-world use. The chamber is then connectedto a supply of clean air. The chamber exhaust is sampledand analysed for chemicals at various times. Themethods are usually broken down into multiple sectionscovering sample collection and preparation, emissionstesting and vapour analysis. The most important ‘horizontal’ reference methods foremissions testing have been developed by theInternational Organization for Standardization (ISO) andare now available as parts 6, 9, 10 and 11 of ISOstandard 16000. ASTM standards D5116, D5197, D6196and D7143 are also important. CEN TC 351 is in theprocess of amalgamating and validating ISO 16000series standards under mandate M/366 of the CPD.Once this work is completed, chemical emissions testing,per TC 351-validated methods, will become a mandatorypart of CE marking for construction products, first underthe CPD and subsequently under the CPR.Reference methods for emissions testing typically includeguidance on the following:

• How to collect and prepare samples ofmaterials/product to test.

• What sort of emissions test chamber equipment touse and what conditions to apply (loading,temperature, humidity, air flow, etc.).

• When to collect and measure the emissions(typically after 3, 12 and/or 28 days).

• How to collect and analyse the chemicals emittedby the sample, and how to use the results tocalculate product emission levels. Two mainapproaches are used for this: 1 (S)VOC analysis: Sampling onto sorbent tubes

with subsequent thermal desorption (TD) andGC/MS analysis for volatile and semi-volatileorganic compounds (VOCs and SVOCs).

2 Formaldehyde: Sampling onto DNPH cartridgeswith subsequent liquid chromatography (HPLC)analysis.

Some construction products generate very complex(S)VOC emission profiles comprising multiple individualcompounds. An example GC/MS data set is shown inFigure 1.

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Product approvals and labelling schemesBefore a reference method can be implemented by anaccredited laboratory, it must be adopted into a productapproval protocol. Certification protocols specify the testmethod plus additional requirements, such as when itshould be carried out, which compounds to target and,

most importantly, pass/fail criteria (i.e. limit levels foremissions).Key national emissions test protocols include the GermanAgBB scheme, the French AFFSET scheme, the FinnishM1 label and the Californian specification 01350. Thereare also many voluntary, sector-specific emissionslabelling schemes like the GUT carpet label or EMICODEfor adhesives. A schematic of the AgBB approval processis shown in Figure 2 as an example. The AgBB scheme,AFFSET protocol and 01350 specification includeextensive and regularly updated lists of 150 or moretarget chemicals plus class 1 and 2 carcinogens.Harmonising the large number of protocols used today isextremely challenging due to the history and vestedinterests of the proponents of each individual label;however, harmonisation is crucial to the success of CEmarking. It is also essential for ensuring manufacturersare not required to carry out multiple similar tests on thesame products to get the broad approval they need forglobal distribution.


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Figure 1: Complex chemical emission profile from aflooring product analysed by TD-GC/MS

Figure 2: Flow chart for the evaluation of VOC and SVOC emissions from building products under theGerman AgBB scheme

There are a number of European and internationalinitiatives currently working on harmonisation of productapproval criteria, most notably an EC expert group underthe umbrella of the Joint European Research Centre atIspra in Italy. By the time the CPR is adopted andstandard validation work within CEN TC 351 iscompleted, it is expected that a harmonised productapproval process will be available for CE marking andthat it will follow the general principles of the GermanAgBB, the French AFFSET protocol and the Californian01350 specification. It is further expected that, inEurope, relevant product-related technical committeeswithin CEN will be heavily involved in setting specificperformance (pass/fail) criteria for their types of product.Once the core criteria for incorporating emissions testinginto CE marking have been finalised, it is furtherexpected that some of the most important voluntarylabels will sit alongside the CE mark to provide optionaladditional information/product-differentiation.

Fast emissions screening for ‘factoryproduction control’Reference methods are preferred for formal productcertification because they generate analytical data thatrelates most closely to real-world use. However, evenfrom the brief description above, it is clear that thesemethods are time-consuming and complex, i.e. they areexpensive for manufacturers. The time required (severaldays, even weeks) also precludes the use of thesestandard procedures for quality control of production orfor convenient testing of prototype materials underdevelopment. Thus, while there are few that wouldcontest the use of these reference methods for formalproduct certification, there is an additional need for acomplementary rapid and cost-effective emissionsscreening method that could be carried out bymanufacturers. The need for an ‘initial’ or ‘screening’ method tocomplement the formal certification test methods ishighlighted in EC Mandate M/366 of the ConstructionProduct Directive. Once adopted, the CPR will also drivesignificant demand for quick, secondary emissionsscreening as it will stipulate both certification of chemicalemissions by an accredited third party laboratory (usingreference methods) plus routine factory productioncontrol. US regulations, such as the California AirResources Board (CARB) Formaldehyde Rule, also requireproducers to monitor conformity with emission levels on aroutine basis.Historically, screening methods for VOCs have eitherinvolved GC/MS analysis of the ‘volatile’ content ofproducts applied as liquids (e.g. ISO 11890-2 for

measuring the organic content of paint) or direct thermaldesorption with GC/MS analysis of small solid or liquidsamples (see Figures 3 and 4). However, it can bedifficult to correlate such VOC ‘content’ data with resultsfrom reference emissions tests. Manufacturers of paintor paint additives, for example, can design products thatcontain solvent, but in which the solvent is encapsulatedsuch that it can never escape to the indoor environment.Content testing is also generally unsuitable as a guide toemissions from composite products, e.g. laminatedmaterials.

Micro-chamber technology was pioneered by MarkesInternational to address industry’s need for a fastemissions screening method that correlates withreference tests. ‘Micro-chambers’ are scaled-downversions of the larger chambers; they are based on thesame fundamental principles and can be used forsurface-only or bulk emissions testing, but are typically


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Figure 3: Artificial leather analysed for VOC content usingdirect TD with GC/MS

Figure 4: Analysing the solvent content of water-basedpaint using direct TD with GC/MS

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operated at slightly elevated temperatures (30–65ºC) tospeed up equilibration. Micro-chamber data producedwithin 30–40 minutes of sample preparation provide areliable indicator of longer term emissions test results formany products 2, 3, thus making it an ideal tool for rapidemissions screening. Relevant industrial applicationsinclude:

• Factory production control of emissions (qualitycontrol)

• In-house checks on emission profiles across aproduct range; different colours, finishes, etc.

• R&D of low emission products• Monitoring the quality of raw materials• Comparison with competitive products• Micro-chamber methods for emission screening are

currently under development by leading standardsagencies to complement longer-term referencetests. Key examples are listed 4–7.

Figure 5: Schematic of the Markes micro-chamber

Micro-Chamber/Thermal Extractor (µ-CTE)technology from Markes InternationalMarkes µ-CTE technology is available in two rugged andportable configurations which are both suitable for use inindustrial laboratories. The smaller unit comprises six44.5 mL chambers (45 mm I.D. x 28 mm depth;represented in Figure 5) and operates at a maximumtemperature of 120°C (M-CTE120). The larger unithouses four 114 mL chambers (64 mm I.D. x 36 mmdepth) and operates at a maximum temperature of250°C (M-CTE250; Figure 6). The chambers themselvesare available in polished stainless steel, or can be inert(Silco)-coated for compatibility with reactive chemicals(e.g. odorous compounds). User-selectable parametersinclude equilibration time, sampling time, temperatureand gas flow rate.

Figure 6: Micro-Chamber/Thermal Extractor (M-CTE250)from Markes International

The µ-CTE is easy to use and requires minimal samplepreparation. Circular samples are typically punched orcut out of planar materials and placed into separatechambers, such that the upper (emitting) surface israised up to the circular baffle (collar) projecting downfrom the chamber lid. This eliminates interference fromedge and rear surface emissions. Irregular materials(such as polymer beads or moulded components) aresimply placed or weighed into individual chambers, andliquid or resinous materials are prepared on suitablesubstrates in the normal way. The temperature of themicro-chamber is typically set above ambient (30–65ºC)to speed up equilibration and optimise sensitivity withoutsignificantly changing the emission profile. Proprietarytechnology 8 controls a constant flow of clean, dry gas orair to each chamber, allowing four or six samples to betested simultaneously. The flow remains constantwhether or not vapour sampling devices (sorbent tubes


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or DNPH cartridges) are connected to the chamberoutlets. No pumps or electronic mass flow controlequipment are required, which makes the system veryeasy to use. Typical gas/air flow rates are 50 mL/min forVOC analysis or 250 mL/min for formaldehyde. Thevapour sampling devices are subsequently analysed byTD-GC/MS or HPLC, respectively, in the normal way.Once samples have been introduced to the micro-chamber pots they are then placed into a µ-CTE unit atthe prescribed temperature, the lids are closed and thegas/air supply turned on. The samples are then left toequilibrate for 20–30 minutes (longer if semi-volatilesare of interest). Vapour sampling tubes are connected tothe outlet of each chamber at the end of theequilibration period, and VOCs are typically collected for15 minutes. This allows VOC emissions to be tested fromfour or six samples per hour, depending on which µ-CTEunit is used. Testing formaldehyde or SVOC emissionsmay take slightly longer, depending on emission ratesand the range of compounds of interest. Markes’ fourchamber µ-CTE can also be used for SVOC emissiontesting according to ISO 16000-25 9.As an example, the VOC emissions from a sample ofplasterboard tested using the µ-CTE, followed byTD–GC/MS, is shown in Figure 7.A more detailed description of µ-CTE operation and performance ispresented in the Markes International publication TDTS 67.

Simplifying data interpretation andanalysisAn additional way in which emissions screening can besimplified, particularly for less experienced industriallaboratories, is to deskill the interpretation of thecomplex emission profiles. ALMSCO International (adivision of Markes) has developed an innovative newsoftware tool, TargetView™, to automatically detectmultiple target compounds in complex TD-GC/MS datasets, even if the compounds of interest are at trace levels(Figure 8). This new software aids comparison withcontrol levels, thus simplifying rapid and reliable pass/failassessment.Figure 8 shows the plasterboard emission data seen inFigure 7 with the application of TargetView toautomatically identify target components present. Targetcompounds and unknown compounds are represented byred bars, the height of which gives an indication of peakarea. The software harnesses two separate powerfulmathematical algorithms to deconvolute and analyse themass spectral data to automatically detect targetcompounds. Data processing takes about a minute perfile (see TDTS 89 for more information). When complete,TargetView produces a simple report for the sample,listing every detected target compound and theassociated degree of confidence (Figure 9).


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Figure 7: Chemical emission profile from a plasterboard product using the µ-CTEwith TD-GC/MS analysis


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Comparison of automatic data analysis by TargetViewversus lengthy, manual data interpretation by a GC/MSexpert has confirmed that TargetView processing is atleast as reliable.As TargetView leaves original data files intact andunaffected, these can be used for TVOC calculations. Noinformation is lost or compromised by TargetView.

ConclusionManufacturers need to be aware of, but not alarmed by,current regulatory developments in the constructionproducts sector and how these changes could impacttheir business. As well as third party certification ofproducts, the requirement for factory production controlof product emissions means that most companies willwant to implement some sort of emissions testing in-house. Markes has focused considerable developmentefforts on producing technology such as the µ-CTEsampling unit and TargetView software, which can beused for rapid screening of product emissions whilemaintaining data quality and correlation with referenceemissions methods in compliance with regulatoryrequirements.These innovations will not only minimise the burden ofroutine quality control of emissions, but will also allowmanufacturers to assess emission levels from prototypeproducts in R&D. This will ultimately speed updevelopment of new, higher-value ‘green’ product ranges,thus protecting consumers and giving the company acompetitive edge over manufacturers of cheaper, high-emission imports.

*

Figure 8a: TargetView interface. Upper pane - Plasterboard emission profile (asFigure 7) with automatic detection of target peaks (red bars). Lower pane -

Detection of trimethyl benzene and corresponding match coefficient.

Figure 8b. Enlarged view ofhighlighted area showing the

target compound trimethylbenzene (*) co-eluting with

multiple compounds in asmall peak

Figure 9: Automated post-run report displaying target hits

References1. ECHA: Guidance on requirements for substances in

articles. (http://echa.europa.eu/reach_en.asp)2. Schripp T., Nachtwey B., Toelke J., Salthammer T.,

Uhde E., Wensing M. and Bahadir M. (2007) Amicro-scale device for testing emissions frommaterials for indoor use. Analytical andBioanalytical Chemistry 387 (5): 1907–1919.

3. PARD Report: Williams GJ, Pharaoh M (2009)Correlation between the VDA 276 test and micro-chamber testing. Issued by WMG, University ofWarwick, UK.

4. ASTM WK22044: New Practice for Rapid Screeningof VOC Emissions from Products Using Micro-scalechambers.

5. ISO WD 12219-3: Indoor Air of Road Vehicles -Part 3: Screening method for the determination ofthe emissions of volatile organic compounds (VOC)from car trim components - Micro-scale chambermethod.

6. The GUT label(http://www.pro-dis.info/gut.html?&L=0)

7 VDI 2083 (http://www.vdi.de/index.php?id=4376) 8. UK patent application 0501928.69. ISO 16000-25: Indoor air - Part 25: Determination

of the emission of semi-volatile organic compoundsby building products - Micro-chamber method.(http://www.iso.org/iso/catalogue_detail.htm?csnumber=44892)

TrademarksMicro-Chamber/Thermal Extractor™ & µ-CTE™ aretrademarks of Markes International Ltd, UKTargetView™ is a trademark of ALMSCO International, UK(a division of Markes International)


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