1、Designation: D 4096 91 (Reapproved 2003)Standard Test Method forDetermination of Total Suspended Particulate Matter in theAtmosphere (HighVolume Sampler Method)1This standard is issued under the fixed designation D 4096; the number immediately following the designation indicates the year oforiginal
2、adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method provides for sampling a large volumeof atmosphere,
3、 1600 to 2400 m355 000 to 85 000 ft3, bymeans of a high flow-rate vacuum pump at a rate of 1.13 to1.70 m3/min 40 to 60 ft3/min (1, 2, 3 and 4).21.2 This flow rate allows suspended particles having diam-eters of less than 100 m (stokes equivalent diameter) to becollected. However, the collection effi
4、ciencies for particleslarger than 20 m decreases with increasing particle size and itvaries widely with the angle of the wind with respect to theroof ridge of the sampler shelter and with increasing speed (5).When glass fiber filters are used, particles within the size rangeof 100 to 0.1 m diameters
5、 or less are ordinarily collected.1.3 The upper limit of mass loading will be determined byplugging of the filter medium with sample material, whichcauses a significant decrease in flow rate (see 6.4). For verydusty atmospheres, shorter sampling periods will be necessary.The minimum amount of partic
6、ulate matter detectable by thismethod is 3 mg (95 % confidence level). When the sampler isoperated at an average flow rate of 1.70 m3/min 60 ft3/min for24 h, this is equivalent to 1 to 2 g/m3(3).1.4 The sample that is collected may be subjected to furtheranalyses by a variety of methods for specific
7、 constituents.1.5 Values stated in SI units shall be regarded as thestandard. Inch-pound units are shown for information only.1.6 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 ap
8、pro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 1356 Terminology Relating to Sampling and Analysis ofAtmospheresD 3631 Test Methods for Measuring Surface AtmosphericPressureE1 Specification fo
9、r ASTM Liquid-in-Glass Thermometers2.2 Other Documents:EPA-600/9-76-005 Quality Assurance Handbook for AirPollution Measurement Systems, Vol I, Principles (De-cember 1984 Rev.)4EPA-600/4-77-027a Quality Assurance Handbook for AirPollution Measurement Systems, Vol II, Ambient AirSpecific Methods43. T
10、erminology3.1 DefinitionsFor definitions of other terms used in thistest method, refer to Terminology D 1356.3.2 Descriptions of Terms:3.2.1 absolute filtera filter or filter medium of ultra-highcollection efficiency for very small particles (submicrometresize) so that essentially all particles of i
11、nterest or of concern arecollected. Commonly, the efficiency is in the region of 99.95 %or higher for a standard aerosol of 0.3-m diameter (seePractice D 2986).3.2.2 Hi-Vol (The High-Volume Air Sampler)a device forsampling large volumes of an atmosphere, collection of thecontained particulate matter
12、 by filtration, and consisting of ahigh-capacity air mover, a filter to collect suspended particles,and means for measuring, or controlling, or both, the flow rate.3.2.3 primary flow-rate standarda device or means ofmeasuring flow rate based on direct primary observations, suchas time and physical d
13、imensions.1This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct responsibility of Subcommittee D22.03 on AmbientAtmospheres and Source Emissions.Current edition approved April 10, 2003. Published June 2003. Originallyapproved in 1982. Last previous edition
14、 approved in 1997 as D 4096 91 (1997)e1.2The boldface numbers in parentheses refer to the list of references at the end ofthis practice.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume in
15、formation, refer to the standards Document Summary page onthe ASTM website.4Available from U.S. Environmental Protection Agency, Environmental Moni-toring Systems Laboratory, QualityAssurance Division, Research Triangle Park, NC27711. Attn: Distribution Record System.1Copyright ASTM International, 1
16、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.4 secondary flow-rate standardA flow-rate-measuringdevice, such as an orifice meter, that has been calibratedagainst a primary standard.3.2.5 spirometera displacement gasometer consisting ofan inverted bell restin
17、g upon or sealed by liquid (or othermeans) and capable of showing the amount of gas added to orwithdrawn from the bell by the displacement (rise or fall) of thebell.3.2.6 working flow-rate standarda flow rate measuringdevice, such as an orifice meter, that has been calibratedagainst a secondary flow
18、-rate standard. The working flow-ratestandard is used to calibrate a flow measuring or flow rateindicating instrument.3.2.7 constant flow high-volume samplera high volumesampler that is equipped with a constant flow control device.4. Summary of Test Method4.1 This test method describes typical equip
19、ment, opera-tional procedures, and a means of calibration of the equipmentusing an orifice flowrate meter. (See also Annex A1.)4.2 Air is drawn into a covered housing and through a filterby means of a high-flow-rate air mover, so that particulatematerial collects on the filter surface.4.3 The amount
20、 of particulate matter accumulated on thefilter over a specified period of time is measured by weighinga preweighed filter after exposure. The flow rate of air sampledis measured over the test period. The result is expressed interms of particulate mass collected (or loading) per unit volumeof air sa
21、mpled, usually as micrograms per cubic metre (g/m3).The volume of air sampled is recorded by measurement of thedevice flow rate(s).4.4 The volume of air sampled is determined by means of aflow-rate indicator. The instrument flow-rate indicator is cali-brated against a reference orifice meter. The la
22、tter is a workingstandard which, in turn, has been calibrated against a secondaryflow meter certified by the U.S. National Institute of Standardsand Technology.4.5 Airborne particulate matter retained on the filter may beexamined or analyzed by a variety of methods. Specificprocedures are not includ
23、ed in this method but are the subjectof separate standard methods.5. Significance and Use5.1 The Hi-Vol sampler is commonly used for the collectionof the airborne particulate component of the atmosphere. Somephysical and chemical parameters of the collected particulatematter are dependent upon the p
24、hysical characteristics of thecollection system and the choice of filter media. A variety ofoptions available for the Hi-Vol sampler give it broad versa-tility and allow the user to develop information about the sizeand quantity of airborne particulate material and, using subse-quent chemical analyt
25、ical techniques, information about thechemical properties of the particulate matter.5.2 This test method presents techniques that when uni-formly applied, provide measurements suitable for intersitecomparisons.5.3 This test method measures the atmosphere presented tothe sampler with good precision,
26、but the actual dust levels inthe atmosphere can vary widely from one location to another.This means that sampler location may be of paramountimportance, and may impose far greater variability of resultsthan any lack of precision in the method of measurement. Inparticular, localized dust sources may
27、exert a major influenceover a very limited area immediately adjacent to such sources.Examples include unpaved streets, vehicle traffic on roadwayswith a surface film of dust, building demolition and construc-tion activity, or nearby industrial plants with dust emissions. Insome cases, dust levels me
28、asured close to such sources may beseveral times the community wide levels exclusive of suchlocalized effects (see Practice D 1357).6. Interferences6.1 Large extraneous objects, such as insects, may be sweptinto the filter and become weighed unnoticed.6.2 Liquid aerosols, such as oil mists and fog d
29、roplets, areretained by the filter. If the amount of liquid so collected issizable, the filter can become wet and its function and massimpaired.6.3 Any gaseous or vaporous constituent of the atmosphereunder test that is reactive with or sorptive upon the filter or itscollected matter will be retaine
30、d and weighed as particulatematter.6.4 As the filter becomes loaded with collected matter, thesampling rate is reduced. If a significant drop in flow rateoccurs, the average of the initial and final flow rate calculatedin 10.1 will not give an accurate estimate of total flow duringthe sampling perio
31、d. The magnitude of such errors will dependon the amount of reduction of airflow rate and on the variationof the mass concentration of dust with time during the 24-hsampling period. As an approximate guideline, any sampleshould be suspect if the final flow rate is less than one half theinitial rate.
32、 A continuous record of flow rate will indicate theoccurrence of this problem, or a constant-flow high-volumesampler may be used to eliminate the problem.6.5 The possibility of power failure or voltage changeduring the test period would lead to an error, depending on theextent and time duration of s
33、uch failure.Acontinuous record offlow rate is desirable.6.6 The passive loading of the filter that can occur if it is leftin place for any time prior to or following a sampling periodcan introduce significant error. For unattended operation, asampler equipped with shutters shall be used.6.7 If two o
34、r more samplers are used at a given location,they should be placed at least2m6ftapart so that onesampler will not affect the results of an adjacent sampler.6.8 Wind tunnel studies have shown significant possiblesampling errors as a function of sampler orientation in atmo-spheres containing high rela
35、tive concentrations of large par-ticles (5).6.9 Metal dusts from motors, especially copper, may sig-nificantly contaminate samples under some conditions.6.10 Under some conditions, atmospheric SO2and NOxmay interfere with the total mass determination (6).7. Apparatus7.1 The essential features of a t
36、ypical high-volume samplerare shown in the diagram of Fig. 1 and Fig. 2. It is a compactD 4096 91 (2003)2unit consisting of a protective housing, an electric motor-driven, high-speed, high-volume air mover, a filter holdercapable of supporting a 203 by 254-mm 8 by 10-in. filter atthe forward or entr
37、ance end, and at the exit end, means foreither indicating or controlling the air flow rate, or both, overthe range of 1.13 to 1.70 m3/min 40 to 60 ft3/min. Designsalso exist in which a flow controller is located between thefilter and the blower. For unattended operation, a samplerequipped with shutt
38、ers to protect the filter is required.7.2 A calibrator kit is required. This contains a workingflow-rate standard of appropriate range in the form of an orificewith its own calibration curve. The kit includes also a set offive flow-control plates. These kits are available from mostsupply houses that
39、 deal in apparatus for air sampling andanalysis.7.3 A large desiccator or air conditioned room is requiredfor filter conditioning, storage, and weighing. Filters must bestored and conditioned at a temperature of 15 to 27C and arelative humidity between 0 and 50 %.7.4 An analytical balance capable of
40、 reading to 0.1 mg, andhaving a capacity of at least5gisnecessary. It is very desirableto have a weighing chamber of adequate size with a supportthat is capable of accommodating the filter without rolling orfolding it or exposing it to drafts during the weighing opera-tion.7.5 Barograph or Barometer
41、, capable of measuring to thenearest 0.1 kPa 1 mm Hg meeting the requirements of TestMethods D 3631.7.6 ThermometerASTM Thermometer 33C, meeting therequirements of Specification E1.7.7 Clock, capable of indicating 24 h 6 2 min.7.8 Flow-Rate Recorder, capable of recording to the nearest0.03 m3/min 1.
42、0 ft3/min.7.9 Differential Manometer, capable of measuring to 4 kPa40 mm Hg.8. Reagents and Materials8.1 Filter Medium:8.1.1 In general, the choice of a filter medium will dependon the purpose of the test. For any given standard test methodthe appropriate medium will be specified. However, it isimpo
43、rtant to be aware of certain filter characteristics that canaffect selection and use.8.1.2 Glass-Fiber Filter MediumThis type is most widelyused for determination of mass loading. Weight stability withrespect to moisture is an attractive feature. High-efficiency orabsolute types are preferred and wi
44、ll collect all airborneparticles of practically every size and description. The follow-ing characteristics are typical:Fiber content All-glass-usually mixed sizesBinder Below 5 % (zero for binderless types)Thickness Approximately 0.5 mmPinholes NoneDOP smoke test (PracticeD 2986)0.05 % penetration,
45、981 Pa 100 mm of waterat 8.53 m/min 28 ft/minParticulate matter collected on glass-fiber medium can beanalyzed for many constituents. If chemical analysis is con-templated binderless filters should be used. It must be borne inmind, however, that glass is a commercial product generallycontaining test
46、-contaminating materials. The high ratio ofsurface area to glass volume permits extraction of suchcontaminants, especially if strong reagents are employed.8.1.3 Silica Fiber FiltersWhere it may be required ordesirable to use a mineral fiber filter, which may later beextracted by strong reagents, sil
47、ica fiber filters can be used.Such fibers are usually made by leaching glass fibers withstrong mineral acids followed by washing with deionizedwater. The fibers are rather weak but can be formed into filtersheets using little or no binder. These filters are commerciallyavailable (7).8.1.4 Cellulose
48、PapersFor some purposes it is desirableto collect airborne particles on cellulose fiber filters. Low-ashpapers are especially useful where the filter is to be destroyedby ignition or chemical digestion. However, these papers havehigher flow resistance (lower sampling rate) and have beenreported to h
49、ave much poorer collection efficiency than theglass fiber media (8). Furthermore, cellulose is very sensitive tomoisture conditions and even with very careful conditioningbefore and after sampling it is difficult to make an accurateweighing of the collected particles. It is usually necessary to dothe weighing with the filter enclosed in a lightweight metal canwith a tight lid.9. Procedure9.1 The Hi-Vol sampler can be used in a number of ways.Variations of procedure may include the kind of filter medium,the surface area of the filter, flow vel
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