1、Designation: D7706 17Standard Practice forRapid Screening of VOC Emissions from Products UsingMicro-Scale Chambers1This standard is issued under the fixed designation D7706; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice describes a micro-scale chamber apparatusand associated procedures for rapidly screening materials an
3、dproducts for their vapor-phase emissions of volatile organiccompounds (VOCs) including formaldehyde and other carbo-nyl compounds. It is intended to complement, not replacereference methods for measuring chemical emissions forexample, small-scale chamber tests (Guide D5116) and emis-sion cell tests
4、 (Practice D7143).1.2 This practice is suitable for use in and outside oflaboratories, in manufacturing sites and in field locations withaccess to electrical power.1.3 Compatible material/product types that may be tested inthe micro-scale chamber apparatus include rigid materials,dried or cured pain
5、ts and coatings, compressible products, andsmall, irregularly-shaped components such as polymer beads.1.4 This practice describes tests to correlate emission resultsobtained from the micro-scale chamber with results obtainedfrom VOC emission reference methods (for example, GuideD5116, Test Method D6
6、007, Practice D7143, and ISO 16000-9and ISO 16000-10).1.5 The micro-scale chamber apparatus operates at moder-ately elevated temperatures, 30C to 60C, to eliminate theneed for cooling, to reduce test times, boost emission rates, andenhance analytical signals for routine emission screening, andto fac
7、ilitate screening of semi-volatile VOC (SVOC) emissionssuch as emissions of some phthalate esters and other plasticiz-ers.1.6 Gas sample collection and chemical analysis are depen-dent upon the nature of the VOCs targeted and are beyond thescope of this practice. However, the procedures described in
8、Test Method D7339, Practice D6196 and ISO 16000-6 foranalysis of VOCs and in Test Method D5197 and ISO 16000-3for analysis of formaldehyde and other carbonyl compoundsare applicable to this practice.1.7 The values stated in SI units are to be regarded asstandard. No other units of measurement are in
9、cluded in thisstandard.1.8 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior
10、 to use.1.9 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBar
11、riers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD1914 Practice for Conversion Units and Factors Relating toSampling and Analysis of AtmospheresD5116 Guide for Small-Scale Environmental Chamber De-terminations
12、of Organic Emissions from Indoor Materials/ProductsD5197 Test Method for Determination of Formaldehyde andOther Carbonyl Compounds inAir (Active Sampler Meth-odology)D5337 Practice for Flow Rate Adjustment of Personal Sam-pling PumpsD6007 Test Method for Determining Formaldehyde Concen-trations in A
13、ir from Wood Products Using a Small-ScaleChamberD6196 Practice for Choosing Sorbents, Sampling Param-eters and Thermal Desorption Analytical Conditions forMonitoring Volatile Organic Chemicals in AirD7143 Practice for Emission Cells for the Determination ofVolatile Organic Emissions from Indoor Mate
14、rials/Products1This practice is under the jurisdiction of ASTM Committee D22 on Air Qualityand is the direct responsibility of Subcommittee D22.05 on Indoor Air.Current edition approved May 1, 2017. Published June 2017. Originallyapproved in 2011. Last previous edition approved in 2011 as D7706 11.
15、DOI:10.1520/D7706-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr H
16、arbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommend
17、ations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1Mon Apr 30 24 D7339 Test Method for Determination of Volatile OrganicCompounds Emitted from Carpet using a Specific SorbentTube and Thermal Desorption / Gas Chromatography2.2 ISO Standards:3ISO 16000-3 Determi
18、nation of formaldehyde and other car-bonyl compounds Active sampling methodISO 16000-6 Determination of volatile organic compoundsin indoor and test chamber air by active sampling onTenax TA sorbent, thermal desorption and gas-chromatography using MS/FIDISO 16000-9 Indoor airPart 9: Determination of
19、 the emis-sion of volatile organic compounds Emission testchamber methodISO 16000-10 Indoor airPart 10: Determination of theemission of volatile organic compounds Emission testcell method2.3 Other Standard:4U.S. EPA Method TO-17 Determination of volatile organiccompounds in ambient air using active
20、sampling ontosorbent tubes3. Terminology3.1 DefinitionsFor definitions and terms commonly usedfor sampling and analysis of atmospheres, refer to TerminologyD1356. For definitions and terms commonly used when testingmaterials and products for VOC emissions, refer to GuideD5116. For an explanation of
21、general units, symbols andconversion factors, refer to Practice D1914.3.2 Definitions of Terms Specific to This Standard:3.2.1 micro-scale test chamber, nan environmental testchamber ranging in volume from a few milliliters to about 250mL and designed to operate at moderately elevated tempera-tures
22、that is used to measure vapor-phase organic emissionsfrom small specimens of solid materials and products.3.2.2 control level, na user-defined acceptance criterionfor a micro-scale chamber test, for example, presence orabsence of a target compound and/or a concentration oremission rate of a target c
23、ompound, typically used in produc-tion quality control to indicate that the tested product samplelikely will meet the corresponding acceptance criterion for areference test.4. Principles4.1 Micro-scale test chambers operate under the same masstransfer principles as conventional small-scale test cham
24、bersand cells for measuring emissions of VOCs including formal-dehyde and other carbonyl compounds from materials andproducts (see Guide D5116 and Practice D7143).4.2 Clean gas (dry nitrogen or air) is supplied to a micro-scale chamber and passes over the exposed surface of the testspecimen before r
25、eaching the exhaust point. The gas flow rateand temperature within the micro-scale chamber are controlled.As the gas passes over the test specimen, emitted compoundsare swept away from the surface.4.3 After the test specimen has equilibrated in the micro-scale chamber (typically for 2040 minutes), a
26、 sampling deviceis connected to the outlet for collection of vapor-phase com-pounds exiting the chamber.5. Summary of Practice5.1 Micro-scale chambers can be used for rapid screeningand quality control of VOC emissions from many materials andproducts. Compatible sources include (with examples): rigi
27、dmaterials (plastics, wood-based panels, hard surface flooring),compressible materials (textiles, foams, polymer sheeting),irregularly-shaped materials (polymer components, carpet),and wet-applied products in dried or cured form (for example,paints, coatings, adhesives, caulks, sealants).5.2 Represe
28、ntative test specimens are prepared frommaterial/product samples and are placed directly into micro-scale chambers. For samples that are heterogeneous, it isnecessary to prepare and test replicate specimens. In somecases, it may be necessary to precondition samples or speci-mens prior to testing.5.3
29、 Micro-scale chambers typically are used for measuringarea-specific emissions from surfaces. They also can be used todetermine mass-, length- or unit-specific emission rates fromvariously shaped test specimens.5.4 Chamber bodies are held at moderately elevated tem-peratures of 30C to 60C and typical
30、ly are supplied with acontrolled flow of clean, dry gas, either nitrogen or air.5.5 Specific operating procedures are developed for eachtype of material or product. The key parameters of equilibra-tion time, chamber temperature and inlet gas flow rate areoptimized in an iterative process starting fr
31、om typical condi-tions and then confirmed by the analysis of replicate speci-mens.5.6 Gas samples for VOCs are collected at the exhaust ofthe micro-scale chamber. For ease of use, the entire gas flowexiting the chamber typically passes through the samplingdevice.5.7 A number of gas sampling and anal
32、ytical methods arecompatible with micro-scale chambers. VOCs may be col-lected on sorbent tubes and analyzed by thermal desorptiongas chromatography (GC) with mass spectrometry (MS) and/orflame ionization detection (FID) to identify and quantifycompounds as described in Test Method D7339, PracticeD6
33、196, ISO 16000-6 and U.S. EPA Method TO-17. Formal-dehyde and other carbonyl compounds may be sampled andanalyzed as described in Test Method D5197 and ISO 16000-3.Other analytical techniques such as direct-reading instrumentsmay be used if applicable.5.8 This practice describes tests that are used
34、to correlateemission results obtained from micro-scale chambers to refer-ence results from conventional emission test chambers andcells (that is, Guide D5116, Test Method D6007, PracticeD7143). This relationship is then developed and validated toestablish a control level to evaluate whether the samp
35、le is3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.4Available from United States Environmental ProtectionAgency (EPA), WilliamJefferson Clinton Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460,http:/www.epa.gov.D
36、7706 172Mon Apr 30 24 likely to be compliant with guidelines or regulations for VOCemissions that are determined by a reference methodSeeSection 12.6. Significance and Use6.1 Manufacturers increasingly are being asked or requiredto demonstrate that vapor-phase emissions of chemicals ofconcern from t
37、heir products under normal use conditionscomply with various voluntary or regulatory acceptance crite-ria. This process typically requires manufacturers to have theirproducts periodically tested for VOC emissions by independentlaboratories using designated reference test methods (forexample, Test Me
38、thod D6007, ISO 16000-9, and ISO 16000-10). To ensure continuing compliance, manufacturers may optto, or be required to, implement screening tests at the produc-tion level.6.2 Reference methods for testing chemical emissions fromproducts are rigorous and typically are too time-consuming andimpractic
39、al for routine emission screening in a productionenvironment.6.3 Micro-scale chambers are unique in that their small sizeand operation at moderately elevated temperatures facilitaterapid equilibration and shortened testing times. Provided asufficiently repeatable correlation with reference test resu
40、ltscan be demonstrated, appropriate control levels can be estab-lished and micro-scale chamber data can be used to monitorproduct manufacturing for likely compliance with referenceacceptance criteria. Enhanced turnaround time for resultsallows for more timely adjustment of parameters to maintaincons
41、istent production with respect to vapor-phase chemicalemissions.6.4 This practice can also be used to monitor the quality ofraw materials for manufacturing processes.6.5 The use of elevated temperatures additionally facilitatesscreening tests for emissions of semi-volatile VOCs (SVOCs)such as some p
42、hthalate esters and other plasticizers.7. Apparatus7.1 General Description:7.1.1 The micro-scale chamber test apparatus comprises oneor more micro-scale chambers, a means of incubating themicro-scale chamber(s) at controlled temperature, a regulatedclean gas (nitrogen or air) supply system with opti
43、onalhumidification, gas sampling capabilities, and instrumentationfor control, monitoring and recording of conditions.7.1.2 A chamber is typically cylindrical in shape to accom-modate an O-ring seal and ranges in total volume from a fewmilliliters to about 250 mL depending upon the mode ofoperation,
44、 that is, chamber mode for bulk sample emissiontesting and cell mode for surface emission testing of planarspecimens. An example of a typical micro-scale chamberillustrating both modes of operation is shown in Appendix X1.7.1.3 The chamber body and lid assembly are designed to beleak free.7.1.4 A ch
45、amber body often has an integral sample holderthat accommodates a planar test specimen such that the backsurface and edges of the specimen are not exposed to the gasstream. The chamber body also can accommodate irregularlyshaped materials for bulk emission testing.7.1.5 The typical cylindrical shape
46、, small exposed volumeand associated high air change rate of the micro-scale chamber;together with the positioning of the gas inlet and outletperpendicular to the sample surface for a planar specimen(Appendix X1) are designed to optimize turbulence, eliminatestill air and ensure thorough mixing of t
47、he gas within thechamber at the range of flows specified (see 7.4.4). Typicallyall of the gas exiting the chamber outlet passes onto the gassampling device, further ensuring representative sampling.Recovery tests can be used to demonstrate adequate mixing(see 8.7.1).7.2 Construction:7.2.1 The micro-
48、scale chamber body and associated lid areconstructed of polished or inert-coated stainless steel.7.2.2 The gasket or O-ring used to seal the lid to its bodyshould be low absorbing and low emitting at the operatingtemperature (60C) so it does not contribute significantly tobackground VOC concentratio
49、ns (see 10.2). Gaskets andO-rings composed of fluoroelastomer polymers are suitable forthis application.7.2.3 The apparatus is designed for disassembly to facilitatecleaning. The chamber body is removed from the heaterhousing and the gasket or O-ring is removed from the body.7.3 Heating:7.3.1 The chamber body sits in a heater housing that canevenly heat the chamber body and maintain it at controlledtemperatures between 30C and 60C with an accuracy of61C and a precision of 62C at the set temperature. Themicro-scale chamber lid and air/gas supply
