1、Designation: D7706 11D7706 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, t
2、he year 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 apparatus and associated procedures for rapidly screening mat
3、erials andproducts for their vapor-phase emissions of volatile organic compounds (VOCs) including formaldehyde and other carbonylcompounds. It is intended to complement, not replace reference methods for measuring chemical emissions for example,small-scale chamber tests (Guide D5116) and emission ce
4、ll tests (Practice D7143).1.2 This practice is suitable for use in and outside of laboratories, in manufacturing sites and in field locations with access toelectrical power.1.3 Compatible material/product types that may be tested in the micro-scale chamber apparatus include rigid materials, driedor
5、cured paints and coatings, compressible products, and small, irregularly-shaped components such as polymer beads.1.4 This practice describes tests to correlate emission results obtained from the micro-scale chamber with results obtained fromVOC emission reference methods (for example, Guide D5116, T
6、est Method D6007, Practice D7143, and ISO 16000-9 and ISO16000-10).1.5 The micro-scale chamber apparatus operates at moderately elevated temperatures, 30C to 60C, to eliminate the need forcooling, to reduce test times, boost emission rates, and enhance analytical signals for routine emission screeni
7、ng, and to facilitatescreening of semi-volatile VOC (SVOC) emissions such as emissions of some phthalate esters and other plasticizers.1.6 Gas sample collection and chemical analysis are dependent upon the nature of the VOCs targeted and are beyond the scopeof this practice. However, the procedures
8、described in Test Method D7339, Practice D6196 and ISO 16000-6 for analysis of VOCsand in Test Method D5197 and ISO 16000-3 for analysis of formaldehyde and other carbonyl compounds are applicable to thispractice.1.7 The values stated in SI units are to be regarded as standard. No other units of mea
9、surement are included in this standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylim
10、itations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Te
11、chnical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis of AtmospheresD1914 Practice for Conversion Units and Factors Relating to Sampling and Analysis of AtmospheresD5116 Guide for Small-Scale Environmental Chamber Det
12、erminations of Organic Emissions from Indoor Materials/ProductsD5197 Test Method for Determination of Formaldehyde and Other Carbonyl Compounds inAir (Active Sampler Methodology)D5337 Practice for Flow Rate Adjustment of Personal Sampling PumpsD6007 Test Method for Determining Formaldehyde Concentra
13、tions in Air from Wood Products Using a Small-Scale Chamber1 This practice is under the jurisdiction of ASTM Committee D22 on Air Quality and is the direct responsibility of Subcommittee D22.05 on Indoor Air.Current edition approved March 1, 2011May 1, 2017. Published March 2011June 2017. Originally
14、 approved in 2011. Last previous edition approved in 2011 as D7706 11. DOI: 10.1520/D7706-11.10.1520/D7706-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the sta
15、ndards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurat
16、ely, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
17、1D6196 Practice for Choosing Sorbents, Sampling Parameters and Thermal Desorption Analytical Conditions for MonitoringVolatile Organic Chemicals in AirD5337 Practice for Flow Rate Adjustment of Personal Sampling PumpsD7143 Practice for Emission Cells for the Determination of Volatile Organic Emissio
18、ns from Indoor Materials/ProductsD7339 Test Method for Determination of Volatile Organic Compounds Emitted from Carpet using a Specific Sorbent Tube andThermal Desorption / Gas Chromatography2.2 ISO Standards:3ISO 16000-3 Determination of formaldehyde and other carbonyl compounds Active sampling met
19、hodISO 16000-6 Determination of volatile organic compounds in indoor and test chamber air by active sampling on Tenax TAsorbent, thermal desorption and gas-chromatography using MS/FIDISO 16000-9 Indoor airPart 9: Determination of the emission of volatile organic compounds Emission test chamber metho
20、dISO 16000-10 Indoor airPart 10: Determination of the emission of volatile organic compounds Emission test cell method2.3 Other Standard:4USU.S. EPA Method TO-17 Determination of volatile organic compounds in ambient air using active sampling onto sorbenttubes3. Terminology3.1 DefinitionsFor definit
21、ions and terms commonly used for sampling and analysis of atmospheres, refer to TerminologyD1356. For definitions and terms commonly used when testing materials and products for VOC emissions, refer to Guide D5116.For an explanation of general units, symbols and conversion factors, refer to Practice
22、 D1914.3.2 Definitions of Terms Specific to This Standard:3.2.1 micro-scale test chamber, nan environmental test chamber ranging in volume from a few milliliters to about 150250 mLand designed to operate at moderately elevated temperatures that is used to measure vapor-phase organic emissions from s
23、mallspecimens of solid materials and products.3.2.2 control level, na user-defined acceptance criterion for a micro-scale chamber test, for example, presence or absence ofa target compound and/or a concentration or emission rate of a target compound, typically used in production quality control toin
24、dicate that the tested product sample likely will meet the corresponding acceptance criterion for a reference test.4. Principles4.1 Micro-scale test chambers operate under the same mass transfer principles as conventional small-scale test chambers andcells for measuring emissions of VOCs including f
25、ormaldehyde and other carbonyl compounds from materials and products (seeGuide 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 test specimenbefore reaching the exhaust point. The gas flow rate and temperatu
26、re within the micro-scale chamber are controlled. As the gaspasses over the test specimen, emitted compounds are swept away from the surface.4.3 After the test specimen has equilibrated in the micro-scale chamber (typically for 20-402040 minutes), a sampling deviceis connected to the outlet for coll
27、ection of vapor-phase compounds exiting the chamber.5. Summary of Practice5.1 Micro-scale chambers can be used for rapid screening and quality control of VOC emissions from many materials andproducts. Compatible sources include (with examples): rigid materials (plastics, wood-based panels, hard surf
28、ace flooring),compressible materials (textiles, foams, polymer sheeting), irregularly-shaped materials (polymer components, carpet), andwet-applied products in dried or cured form (for example, paints, coatings, adhesives, caulks, sealants).5.2 Representative test specimens are prepared from materia
29、l/product samples and are placed directly into micro-scalechambers. For samples that are heterogeneous, it is necessary to prepare and test replicate specimens. In some cases, it may benecessary to precondition samples or specimens prior to testing.5.3 Micro-scale chambers typically are used for mea
30、suring area-specific emissions from surfaces. They also can be used todetermine mass-, length- or unit-specific emission rates from variously shaped test specimens.5.4 Chamber bodies are held at moderately elevated temperatures of 30C to 60C and typically are supplied with a controlledflow of clean,
31、 dry gas, either nitrogen or air.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.4 Available from United States Environmental ProtectionAgency (EPA),Ariel Rios William Jefferson Clinton Bldg., 1200 PennsylvaniaAve., NW,
32、 Washington, DC 20460,http:/www.epa.gov.D7706 1725.5 Specific operating procedures are developed for each type of material or product. The key parameters of equilibration time,chamber temperature and inlet gas flow rate are optimized in an iterative process starting from typical conditions and thenc
33、onfirmed by the analysis of replicate specimens.5.6 Gas samples for VOCs are collected at the exhaust of the micro-scale chamber. For ease of use, the entire gas flow exitingthe chamber typically passes through the sampling device.5.7 A number of gas sampling and analytical methods are compatible wi
34、th micro-scale chambers. VOCs may be collected onsorbent tubes and analyzed by thermal desorptiongas chromatography (GC) with mass spectrometry (MS) and/or flameionization detection (FID) to identify and quantify compounds as described in Test Method D7339, Practice D6196, ISO 16000-6and USU.S. EPAM
35、ethod TO-17. Formaldehyde and other carbonyl compounds may be sampled and analyzed as described in TestMethod D5197 and ISO 16000-3. Other analytical techniques such as direct-reading instruments may be used if applicable.5.8 This practice describes tests that are used to correlate emission results
36、obtained from micro-scale chambers to referenceresults from conventional emission test chambers and cells (that is, Guide D5116, Test Method D6007, Practice D7143). Thisrelationship is then developed and validated to establish a control level to evaluate whether the sample is likely to be compliantw
37、ith guidelines or regulations for VOC emissions that are determined by a reference methodSee Section 12.6. Significance and Use6.1 Manufacturers increasingly are being asked or required to demonstrate that vapor-phase emissions of chemicals of concernfrom their products under normal use conditions c
38、omply with various voluntary or regulatory acceptance criteria. This processtypically requires manufacturers to have their products periodically tested for VOC emissions by independent laboratories usingdesignated reference test methods (for example, Test Method D6007, ISO 16000-9, and ISO 16000-10)
39、. To ensure continuingcompliance, manufacturers may opt to, or be required to, implement screening tests at the production level.6.2 Reference methods for testing chemical emissions from products are rigorous and typically are too time-consuming andimpractical for routine emission screening in a pro
40、duction environment.6.3 Micro-scale chambers are unique in that their small size and operation at moderately elevated temperatures facilitate rapidequilibration and shortened testing times. Provided a sufficiently repeatable correlation with reference test results can bedemonstrated, appropriate con
41、trol levels can be established and micro-scale chamber data can be used to monitor productmanufacturing for likely compliance with reference acceptance criteria. Enhanced turnaround time for results allows for moretimely adjustment of parameters to maintain consistent production with respect to vapo
42、r-phase chemical emissions.6.4 This practice can also be used to monitor the quality of raw materials for manufacturing processes.6.5 The use of elevated temperatures additionally facilitates screening tests for emissions of semi-volatile VOCs (SVOCs) suchas some phthalate esters and other plasticiz
43、ers.7. Apparatus7.1 General Description:7.1.1 The micro-scale chamber test apparatus comprises one or more micro-scale chambers, a means of incubating themicro-scale chamber(s) at controlled temperature, a regulated clean gas (nitrogen or air) supply system with optionalhumidification, gas sampling
44、capabilities, and instrumentation for control, monitoring and recording of conditions.7.1.2 A chamber is typically cylindrical in shape to accommodate an O-ring seal and ranges in total volume from a fewmilliliters to about 150250 mLdepending upon the mode of operation, that is, chamber mode for bul
45、k sample emission testing andcell mode for surface emission testing of planar specimens. An example of a typical micro-scale chamber illustrating both modesof operation is shown in Appendix X1.7.1.3 The chamber body and lid assembly are designed to be leak free.7.1.4 Achamber body often has an integ
46、ral sample holder that accommodates a planar test specimen such that the back surfaceand edges of the specimen are not exposed to the gas stream.The chamber body also can accommodate irregularly shaped materialsfor bulk emission testing.7.1.5 The typical cylindrical shape, small exposed volume and a
47、ssociated high air change rate of the micro-scale chamber;together with the positioning of the gas inlet and outlet perpendicular to the sample surface for a planar specimen(Annex(Appendix X1 A) ) are designed to optimize turbulence, eliminate still air and ensure thorough mixing of the gas withinth
48、e chamber at the range of flows specified (see 7.4.4). Typically all 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-scale chambe
49、r body and associated lid are constructed of polished or inert-coated stainless steel.7.2.2 The gasket or O-ring used to seal the lid to its body is should be low absorbing and low emitting at the operatingtemperature (60C) so it does not contribute significantly to background VOC concentrations.concentrations (see 10.2). Gasketsand O-rings composed of fluoroelastomer polymers are suitable for this application.D7706 1737.2.3 The apparatus is designed for easy disassembly to facilitate cleaning. The chamber body is easily removed from the heaterhousing and
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