1、Designation:D6877131Standard Test Method forMonitoring Diesel Particulate Exhaust in the Workplace1This standard is issued under the fixed designation D6877;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A
2、number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1NOTEEditorial changes were submitted after publication in October 2013.1.Scope1.1 This test method covers determination of organic andelemental carbo
3、n(OC and EC)in the particulate fraction ofdiesel engine exhaust,hereafter referred to as diesel particulatematter(DPM).Samples of workplace atmospheres are col-lected on quartz-fiber filters.The method also is suitable forother types of carbonaceous aerosols and has been widelyapplied to environment
4、al monitoring.It is not appropriate forsampling volatile or semi-volatile components.These compo-nents require sorbents for efficient collection.NOTE1Sample collection and handling procedures for environmentalsamples differ from occupational samples.This standard addresses occu-pational monitoring o
5、f DPM in workplaces where diesel-powered equip-ment is used.1.2 The method is based on a thermal-optical technique(1,2).2Speciation of OC and EC is achieved through temperatureand atmosphere control,and an optical feature that corrects forsample charring(carbonization).1.3 A portion of a 37-mm,quart
6、z-fiber filter sample isanalyzed.Results for the portion are used to calculate the totalmass of OC and EC on the filter.The portion must berepresentative of the entire filter deposit.If the deposit isuneven,two or more representative portions should be ana-lyzed for an average.Alternatively,the enti
7、re filter can beanalyzed,in multiple portions,to determine the total mass.Open-faced cassettes give even deposits but may not bepractical.At 2 L/min,closed-face cassettes generally giveresults equivalent to open-face cassettes if other dusts areabsent.Higher flow rates may be employed,but closed-fac
8、edcassettes operated at higher flow rates(for example,5 L/min)sometimes have uneven deposits due to particle impaction atthe center of the filter.Other samplers may be required,depending on the sampling environment(2-5).1.4 The calculated limit of detection(LOD)depends on thelevel of contamination o
9、f the media blanks(5).A LOD ofapproximately 0.2 g carbon per cm2of filter was estimatedwhen analyzing a sucrose standard solution applied to filterportions cleaned immediately before analysis.LODs based onmedia blanks stored after cleaning are usually higher.LODsbased on a set of media blanks analyz
10、ed over a six monthperiod at a commercial laboratory were OC=1.2 g/cm2,EC=0.4 g/cm2,and TC=1.3 g/cm2,where TC refers to totalcarbon(TC=OC+EC).In practice,the LOD estimateprovided by a laboratory is based on results for a set of mediablanks submitted with the samples.To reduce blank variability(due t
11、o lack of loading),a manual OC-EC split is assigned atthe time when oxygen is introduced.With manual splits,theSD for media blanks is typically about 0.02-0.03 g EC/cm2,giving LODs(3 SD blank)from about 0.06-0.09 g EC/cm2.The corresponding air concentration depends on the depositarea(filter size)and
12、 air volume.1.5 OC-EC methods are operational,which means theanalytical procedure defines the analyte.The test method offersgreater selectivity and precision than thermal techniques thatdo not correct for charring of organic components.The analysismethod is simple and relatively quick(about 15 min).
13、Theanalysis and data reduction are automated,and the instrumentis programmable(different methods can be saved as methodsfor other applications).1.6 A method(5040)for DPM based on thermal-opticalanalysis has been published by the National Institute forOccupational Safety and Health(NIOSH).Method upda
14、tes(3,4)have been published since its initial(1996)publication in theNIOSH Manual ofAnalytical Methods(NMAM).Both OC andEC are determined by NMAM 5040.An EC exposure marker(for DPM)was recommended because EC is a more selectivemeasure of exposure.A comprehensive review of the methodand rationale for
15、 selection of an EC marker are provided in aChapter of NMAM(5).1This test method is under the jurisdiction of ASTM Committee D22 on AirQualityand is the direct responsibility of Subcommittee D22.04 on Workplace AirQuality.Current edition approved Oct.1,2013.Published October 2013.Originallyapproved
16、in 2003.Last previous edition approved in 2008 as D6877 03(2008).DOI:10.1520/D6877-13E01.2The boldface numbers in parentheses refer to references at the end of this testmethod.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 1.7 The thermal-optical instrument required for the analysisis manufactured by a private laboratory.3As with mostinstrumentation,design improvements continue to be made.Different laboratories may be using different
