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Designation: D6246 − 08 (Reapproved 2018)Standard Practice forEvaluating the Performance of Diffusive Samplers 1This standard is issued under the f i xed designation D6246; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the 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 covers the evaluation of the performanceof diffusive samplers of gases and vapors for use over samplingperiods from 4 to 12 h and for wind speeds less than 0.5 m/s.Such sampling periods and wind speeds are the most commonin the indoor workplace setting. This practice does not apply tostatic or area sampling in wind speeds less than 0.1 m/s, whendiffusion outside the sampler may dominate needed convectionfrom the ambient air to the vicinity of the sampler. Given asuitable exposure chamber, the practice can be extended tocover sampler use for other sampling periods and conditions.The aim is to provide a concise set of experiments forclassifying samplers primarily in accordance with a singlesampler accuracy f i gure. Accuracy is def i ned (3.2.2) in thisstandard so as to take into account both imprecision anduncorrected bias. Accuracy estimates refer to conditions ofsampler use which are normally expected in a workplacesetting. These conditions may be characterized by thetemperature, atmospheric pressure, humidity, and ambientwind speed, none of which may be constant or accuratelyknown when the sampler is used in the f i eld. Furthermore, theaccuracy accounts for the effects of diffusive loss of analyte onthe estimation of time-weighted averages of concentrationswhich may not be constant in time. Aside from accuracy, thesamplers are tested for compliance with the manufacturer’sstated limits on capacity, possibly in the presence of interferingcompounds.1.2 This practice is an extension of previous research ondiffusive samplers (1-14) 2 as well as Practices D4597, D4598,D4599, and MDHS 27. An essential advance here is theestimation of sampler accuracy under actual conditions of use.Furthermore, the costs of sampler evaluation are reduced.1.3 Knowledge gained from similar analytes expedites sam-pler evaluation. For example, interpolation of data character-izing the sampling of analytes at separated points of ahomologous series of compounds is recommended. At presentthe procedure of (9) is suggested. Following evaluation of asampler in use at a single homologous series member accord-ing to the present practice, higher molecular weight memberswould receive partial validations considering sampling rate,capacity, analytical recovery, and interferences. The test fordiffusive analyte loss can be omitted if the effect is foundnegligible for a given sampler or analyte series.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 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, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 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 TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards: 3D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD4597 Practice for Sampling Workplace Atmospheres toCollect Gases or Vapors with Solid Sorbent DiffusiveSamplersD4598 Practice for Sampling Workplace Atmospheres toCollect Gases or Vapors with Liquid Sorbent DiffusionalSamplers (Withdrawn 1995) 4D4599 Practice for Measuring the Concentration of ToxicGases or Vapors Using Length-of-Stain Dosimeters2.2 International Standards:CEN EN 838 European Standard, WorkplaceAtmospheres –Diffusive Samplers for the Determination of Gases or1 This practice is under the jurisdiction ofASTM Committee D22 on Air Qualityand is the direct responsibility of Subcommittee D22.04 on Workplace Air Quality.Current edition approved Oct. 1, 2018. Published October 2018. Originallyapproved in 1998. Last previous edition approved in 2013 as D6246 – 08 (2013) ?1 .DOI: 10.1520/D6246-08R18.2 The boldface numbers in parentheses refer to the list of references at the end ofthis standard.3 For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at service@astm.org. For Annual Book of ASTMStandards volume information, refer to the standard’s Document Summary page onthe ASTM website.4 The last approved version of this historical standard is referenced onwww.astm.org.Copyright © ASTM International, 100 Barr Harbor 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 Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1