1、Designation: D1357 95(Reapproved 2011)Standard Practice forPlanning the Sampling of the Ambient Atmosphere1This standard is issued under the fixed designation D1357; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、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 The purpose of this practice is to present the broadconcepts of sampling the ambient air for the concentrations ofcontamina
3、nts. Detailed procedures are not discussed. Generalprinciples in planning a sampling program are given includingguidelines for the selection of sites and the location of the airsampling inlet.1.2 Investigations of atmospheric contaminants involve thestudy of a heterogeneous mass under uncontrolled c
4、onditions.Interpretation of the data derived from the air samplingprogram must often be based on the statistical theory ofprobability. Extreme care must be observed to obtain measure-ments over a sufficient length of time to obtain results that maybe considered representative.1.3 The variables that
5、may affect the contaminant concen-trations are the atmospheric stability (temperature-height pro-file), turbulence, wind speed and direction, solar radiation,precipitation, topography, emission rates, chemical reactionrates for their formation and decomposition, and the physicaland chemical properti
6、es of the contaminant. To obtain concen-trations of gaseous contaminants in terms of weight per unitvolume, the ambient temperature and atmospheric pressure atthe location sampled must be known.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use.
7、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 to use.2. Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD3249 Practic
8、e for General Ambient Air Analyzer Proce-duresD3614 Guide for Laboratories Engaged in Sampling andAnalysis of Atmospheres and EmissionsNOTE 1A list of references are appended to this practice whichprovide greater details including background information, air qualitymodeling techniques, and special p
9、urposes air sampling programs (1).33. Terminology3.1 DefinitionsFor definitions of terms used in this prac-tice, refer to Terminology D1356.4. Summary of Practice4.1 This practice describes the general guidelines in plan-ning for sampling the ambient air for the concentrations ofcontaminants.5. Sign
10、ificance and Use5.1 Since the analysis of the atmosphere is influenced byphenomena in which all factors except the method of samplingand analytical procedure are beyond the control of the inves-tigator, statistical consideration must be given to determine theadequacy of the number of samples obtaine
11、d, the length of timethat the sampling program is carried out, and the number ofsites sampled. The purpose of the sampling and the character-istics of the contaminant to be measured will have an influencein determining this adequacy. Regular, or if possible, continu-ous measurements of the contamina
12、nt with simultaneous per-tinent meteorological observations should be obtained duringall seasons of the year. Statistical techniques may then beapplied to determine the influence of the meteorologicalvariables on the concentrations measured (2).5.2 Statistical methods may be used for the interpretat
13、ion ofall of the data available (2). Trends of patterns and relation-ships between variables of statistical significance may bedetected. Much of the validity of the results will depend,however, on the comprehensiveness of the analysis and thelocation and contaminant measured. For example, if 24-hsam
14、ples of suspended particulate matter are obtained onlyperiodically (for example, every 6 or 8 days throughout theyear), the geometric mean of the measured concentrations isrepresentative of the median value assuming the data are lognormally distributed. The geometric mean level may be used to1This p
15、ractice is under the jurisdiction of ASTM Committee D22 on Air Qualityand is the direct responsibility of Subcommittee D22.03 on Ambient Atmospheresand Source Emissions.Current edition approved Oct. 1, 2011. Published October 2011. Originallyapproved in 1955. Last previous edition approved in 2005 a
16、s D1357 - 95 (2005).DOI: 10.1520/D1357-95R11.2For 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.3The boldface nu
17、mbers in parentheses refer to the list of references at the end ofthis practice.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United Spare the air quality at different locations at which suchregular but intermittent observations of suspended par
18、ticulatematter are made.6. Basic Principles6.1 The choice of sampling techniques and measurementmethodology, the characteristics of the sites, the number ofsampling stations, and the amount of data collected all dependon the objectives of the monitoring program. These objectivesmay be one or more of
19、 the following:6.1.1 Air quality assessment including determining maxi-mum concentration,6.1.2 Health and vegetation effects studies,6.1.3 Trend analysis,6.1.4 Evaluation of pollution abatement programs,6.1.5 Establishment of air quality criteria and standards byrelating to effects,6.1.6 Enforcement
20、 of control regulations,6.1.7 Development of air pollution control strategies,6.1.8 Activation of alert or emergency procedures,6.1.9 Land use, transportation, and energy systems plan-ning,6.1.10 Background evaluations, and6.1.11 Atmospheric chemistry studies.6.2 In order to cover all the variable m
21、eteorological condi-tions that may greatly affect the air quality in an area, airmonitoring for lengthy periods of time may be necessary tomeet most of the above objectives.6.3 The topography, demography, and micrometeorology ofthe area as well as the contaminant measured, must beconsidered in deter
22、mining the number of monitoring stationsrequired in the area. Photographs and a map of the locations ofthe sampling stations is desirable in describing the samplingstation.6.4 Unless the purpose of the sampling programs is sitespecific, the sites monitored should, in general, be selected soas to avo
23、id undue influence by any local source that may causelocal elevated concentrations that are not representative of theregion to be characterized by the data.6.5 Monitoring sites for determining the impact on airquality by individual sources should be selected, if possible, soas to isolate the effect
24、of the source being considered. Whenthere are many sources of the contaminant in the area, the sitessampled should be strategically located so that with winddirection data obtained simultaneously near the sites, themonitoring results will provide evidence of the contributions ofthe individual source
25、s. Multiple samplers or monitors operat-ing simultaneously upwind and downwind from the source areoften very valuable and efficient.7. Meteorological Factors7.1 The meteorological parameters that are most importantin an atmospheric sampling program are:7.1.1 Wind direction and speed, the degree of p
26、ersistence indirection, and gustiness;7.1.2 Temperature and its changes with height aboveground; the mixing height, that is, the height above ground thatthe pollutants will diffuse to during the afternoon; and7.1.3 Solar radiation and hours of sunshine, humidity, pre-cipitation, and barometric press
27、ure. These parameters areimportant in assessing the pollution potential of an area andshould be considered in the planning of a monitoring programand in the interpretation of the data. Pertinent meteorologicaland climatological information may be obtained from the localweather department. In many lo
28、calities, however, the micro-meteorology may be unique and meteorological investigationsto provide data specific to the area may be needed.7.2 The influences of each of the meteorological parametersimportant to air quality are discussed in detail. The methods ofcarrying out the related meteorologica
29、l investigations are alsodiscussed (3, 4, 5).8. Topographical Factors8.1 Topography can influence the contaminant concentra-tions in the atmosphere. For example, a valley will causepersistence in wind directions and intensify low-level nocturnalinversions that will limit the dispersion of pollutants
30、 emittedinto it. Mountains or plateaus may act as barriers affecting theflow of air as well as the contaminant concentrations in theirvicinity. Consideration should be given to the influence ofthese features as well as that of large lakes, the sea, and oceans(2, 3).9. Apparatus9.1 Details of the app
31、aratus or instruments employed insampling the air or carrying out associated meteorologicalinvestigations are discussed in other ASTM methods andrecommendations.10. Sampling Procedure and Siting Concepts10.1 The choice of procedure for the air sampling isdependent on the contaminant to be measured.
32、See PracticeD3249 for recommendations for general ambient air analyzerprocedures. ASTM recommended methods have been pub-lished for most of the common contaminants that are sampled.Automatic instruments providing a continuous record of theconcentrations of the contaminant should be utilized whenever
33、possible to save manpower and increase efficiency. Very oftenfactors such as temperature, humidity, and vibrations, as wellas the power line voltage can influence the output of the airmonitoring instrument and these should be controlled.10.2 The monitors must be supplied with sample air thatrepresen
34、ts the ambient air under investigation. Careful consid-eration should be given to the sample conveying system.Aductsystem is often utilized for this purpose. There should be as fewabrupt enlargements and elbows as possible, as these mayaffect the uniformity and hence the concentration of thecontamin
35、ants measured. The material for the duct should besuch that there will be little or no interaction between it and thecontaminants in the air sampled. Employ temperature controlto limit the condensation forming in the sampling lines. Takethe samples from straight sections of the duct with the inletle
36、ad to the monitoring instrument as short as possible.10.3 The following guidelines are recommended for sam-pling locations unless site specific measurements are desired.The height of the inlet to the sampling duct should be normallyD1357 95 (2011)2from 2.5 to 5 m above ground whenever possible. The
37、heightof the inlet above the sampling station structure or vegetationadjacent to the station should be greater than 1 m. Samplingshould preferably be through a vertical inlet with an invertedcone over the opening. For a horizontal inlet, there should bea minimum of 2 m from the face of the structure
38、. For access torepresentative ambient air in the area sampled, the elevationangle from the inlet to the top of nearby buildings should beless than 30. To be representative of the area in which a largesegment of the population is exposed to contaminants emittedby automobiles, the inlet should be at a
39、 distance greater than 15m from the nearest high-volume traffic artery. Photochemicaloxidants or ozone samplers should be located at distancesgreater than 50 m from high traffic locations. Particulate mattersamplers should be sited at locations that are greater than 200m from unpaved streets or road
40、s (6, 7, 8).11. Plan of Sampling Procedure11.1 The procedure for sampling should be undertaken inthe following steps:11.1.1 A general exploratory survey of the area includingthe topography, an inventory of sources for the contaminants,the height of their emissions, traffic, and land use data.11.1.2
41、A preliminary meteorology analysis to identify winddirection frequencies, wind velocity, and temperature-heightprofiles.11.1.3 Exploratory short-term temporary sampling requiresa number of temporary sampling stations, to determine theneed and the best sites for extensive long term monitoring.Using a
42、ir quality models, and the input of emission inventoryand meteorological information for the area obtained in 11.1.1and 11.1.2, an estimate for the levels of air quality over the areamay be calculated. The model results will provide guidance indetermining the locations for monitors that will measure
43、 themaximum levels and the number of monitors required tocharacterize the air quality in the area of concern (9, 10).12. Quality Assurance12.1 Quality assurance programs include all of the activitiesnecessary to provide measurement data at a requisite precisionand accuracy. An air quality assurance
44、program should bedeveloped and implemented for every air monitoring programto ensure compatibility of data both externally and betweenstations in the monitoring network.12.2 Guidelines for quality assurance programs are given inPractice D3614. The quality assurance program should includeall the foll
45、owing elements to the extent to which they areapplicable:12.2.1 Sampling and analytical procedures should be speci-fied, using standard methods such as ASTM methods whereapplicable and appropriate to the objectives to be achieved.12.2.2 Calibration procedures should be specified in thestandard metho
46、ds. For a continuing program, frequency ofcalibration re-checks should be specified.12.2.3 Data collection and recording procedures should bespecified, to identify responsibility for record keeping, analysisof recorder chart records, conversion to computer format, andmethod and frequency of reportin
47、g. Specifications should alsobe included for safeguarding equipment, samples, and recordsto maintain the chain of evidence if data are required for legalpurposes.12.2.4 Sample shipping and storage procedures should bedocumented, especially if the methods used impose any limitson time delay prior to
48、analysis, refrigeration, or other storageconditions, or any other precautions in sample handling.12.2.5 Methods of computation after analysis or automaticdata recording should be specified, including data validationprocedures used to minimize errors in computation or recordkeeping.12.2.6 Independent
49、 audits of the entire measurement pro-gram by an outside agency are helpful, in which parallelsampling and analysis is conducted independently to verify theprecision and accuracy of the final results. Simultaneousanalysis of ambient atmospheres can be used, as well asindependent measurements using cylinder gases or other cali-bration standards.12.2.7 Interlaboratory tests (also called “round-robin” tests)are useful as a means of confirming the precision and accuracyof the methods used, and also make it possible for eachorganization to check its own performance against othe
