1、Designation: D7296 12Standard Practice forCollection of Settled Dust Samples Using Dry WipeSampling Methods for Subsequent Determination ofBeryllium and Compounds1This standard is issued under the fixed designation D7296; 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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers the collection of settled dust con-taining ber
3、yllium and/or beryllium compounds on surfacesusing the dry wipe sampling method. These samples arecollected in a manner that will permit subsequent extractionand determination of beryllium and compounds in the wipesusing laboratory analysis techniques such as atomic spectrom-etry or fluorescence det
4、ection.1.2 This practice is limited in its scope to applications wherewetted wipe sampling (using Practice D6966) or vacuumsampling (using Practice D7144) is not physically feasible (forexample, if the surface to be wiped would be compromised byuse of wetted wipes).1.3 This practice does not address
5、 the sampling designcriteria (that is, sampling plan which includes the number andlocation of samples) that are used for clearance, hazardevaluation, risk assessment, and other purposes. To provide forvalid conclusions, sufficient numbers of samples should beobtained as directed by a sampling plan.A
6、dditional guidance isprovided in Guide D7659.1.4 This practice contains notes that are explanatory and arenot part of the mandatory requirements of this practice.1.5 The values stated in SI units are to be regarded asstandard.1.6 This standard does not purport to address all of thesafety concerns, i
7、f any, associated with its use. 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 Ana
8、lysis ofAtmospheresD4840 Guide for Sample Chain-of-Custody ProceduresD6966 Practice for Collection of Settled Dust SamplesUsing Wipe Sampling Methods for Subsequent Determi-nation of MetalsD7144 Practice for Collection of Surface Dust by Micro-vacuum Sampling for Subsequent Metals DeterminationD7659
9、 Guide for Strategies for Surface Sampling of Metalsand Metalloids for Worker ProtectionD7707 Specification for Wipe Sampling Materials for Be-ryllium in Surface Dust3. Terminology3.1 For definitions of terms not listed here, see TerminologyD1356.3.2 Definitions:3.2.1 batch, na group of field or qua
10、lity control (QC)samples that are collected or processed together at the sametime using the same reagents and equipment.3.2.2 sampling location, na specific area within a sam-pling site that is subjected to sample collection. D69663.2.2.1 DiscussionMultiple sampling locations are com-monly designate
11、d for a single sampling site (see 3.2.3).3.2.3 sampling site, na local geographic area that containsthe sampling locations (see 3.2.2). D69663.2.3.1 DiscussionA sampling site is generally limited toan area that is easily covered by walking.3.2.4 dry wipe, na suitable non-wetted wiping medium.3.2.4.1
12、 DiscussionThese are to be distinguished fromwipes as defined in Practice D6966 and Specification D7707,which are wet wipes.3.3 Definitions of Terms Specific to This Standard:3.3.1 field blank, na dry wipe (see 3.2.4) that is exposedto the same handling as field samples except that no sample iscolle
13、cted (no surface is actually wiped).3.3.1.1 DiscussionAnalysis results from field blanks pro-vide information on the analyte background level in the drywipe, combined with the potential contamination experiencedby samples collected within the batch (see 3.2.1) resulting fromhandling.1This practice i
14、s under the jurisdiction of ASTM Committee D22 on Air Qualityand is the direct responsibility of Subcommittee D22.04 on Workplace Air Quality.Current edition approved . Published May 2012. Originally approved in 2006.Last previous edition approved in 2006 as D7296 - 06. DOI:10.1520/D7296-12.2For ref
15、erenced 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, We
16、st Conshohocken, PA 19428-2959, United States.4. Summary of Practice4.1 Wipe samples of settled dust are collected on surfacesfrom areas of known dimensions with dry wipes satisfyingcertain requirements, using a specified pattern of wiping.4.2 The collected dry wipes are then ready for subsequentsam
17、ple preparation and analysis for the measurement ofberyllium and compounds.5. Significance and Use5.1 This practice is intended for the collection of settled dustsamples for the subsequent measurement of beryllium andcompounds. The practice is meant for use in the collection ofsettled dust samples t
18、hat are of interest in clearance, hazardevaluation, risk assessment, and other purposes.5.2 This practice is intended solely for the collection ofsettled dust samples from hard, relatively smooth nonporoussurfaces that may be compromised by water or other wettingagents and that are therefore not sui
19、table for wet wipe samplingusing Practice D6966 or micro-vacuum sampling using Prac-tice D7144. Use of this practice for any purpose other than theintended purpose is discouraged due to the limited collectionefficiency and high variability of dry wipe sampling as com-pared to wetted wipe or micro-va
20、cuum sampling3.5.3 This practice is less effective for collecting settled dustsamples from surfaces with substantial texture such as roughconcrete, brickwork, textured ceilings, and soft fibrous surfacessuch as upholstery and carpeting. Micro-vacuum samplingusing Practice D7144 may be more suitable
21、for these surfaces.6. Apparatus6.1 Sampling TemplatesOne or more of the following: 10cm by 10 cm (minimum dimensions) reusable or disposablealuminum or plastic template(s), or disposable cardboardtemplates, (full-square, rectangular, square “U-shaped,” rect-angular “U-shaped,” or “L-shaped,” or both
22、); or templates ofalternative areas having accurately known dimensions (seeNote 1). Templates shall be capable of lying flat on a surface.NOTE 1For most surfaces, it is recommended to collect settled dustfrom a minimum surface area of 100 cm2to provide sufficient material forsubsequent laboratory an
23、alysis. However, larger areas (for example, 30 cmby 30 cm) may be appropriate for surfaces having little or no visiblesettled dust, while a smaller sampling area (for example, 10 cm by 10 cm)may be appropriate for surfaces with high levels of visible settled dust. Itis recommended to have a suite of
24、 templates with various samplingdimensions.6.2 Dry Wipes, for collection of settled dust samples fromsurfaces. The background metal(s) content of the dry wipesshould be as low as possible. At a maximum, the backgroundlevel of beryllium shall be no more than one-tenth the targetconcentration to be me
25、asured. Variability of background levelsof beryllium shall not exceed ten times the standard deviationof the mean background level. Dry wipe materials shall becompatible with the anticipated sample preparation and analy-sis methods.NOTE 2Characteristics of dry wipe materials, such as hardness,porosi
26、ty, and thickness, may affect collection efficiency. Quantitativelaboratory filter paper, or wipe media with demonstrated equivalent orsuperior performance, should be used. Consistent use of a single materialis recommended because use of multiple materials may produce widelyvarying results.3For anal
27、ysis by ICP-AES or ICP-MS, dry wipes shouldbe either wholly soluble or wholly insoluble when using the selectedsample preparation method. This is because partially dissolved wipes canmake subsequent handling of sample solutions difficult, or they can causeanalytical errors due to matrix mismatches b
28、etween sample solutions andcalibration solutions, or both. Partially dissolved wipes may be acceptableas long as the undissolved remnant leaves an intact skeleton (that is, ofwoven fabric) that does not adversely affect the sample solution. If thesample preparation method selected involves quantitat
29、ive transfer of thesample solution to volumetric glassware prior to analysis, the wipes usedfor sampling should be completely soluble when using the chosen samplepreparation method.6.3 Sample Containers, sealable, rigid-walled, 15-mL mini-mum volume.NOTE 3Screw-top plastic centrifuge tubes are an ex
30、ample of asuitable rigid-walled sample container.NOTE 4Use of sealable plastic bags for holding and transporting thesettled dust wipe samples is not recommended due to the potential loss ofcollected dust within the plastic bags during transportation and laboratoryhandling. Quantitative removal and p
31、rocessing of the settled dust wipesample by the laboratory is significantly improved through the use ofsealable rigid-walled containers.6.4 Measuring Tool, tape or ruler, capable of measuring tothe nearest 60.1 cm.6.5 Plastic Gloves, powderless.6.6 Cleaning Cloths, for cleaning of templates and othe
32、requipment.NOTE 5Wet wipes that comply with Specification D7707 may be usedfor cleaning templates and other sampling equipment as long as they areallowed to dry thoroughly before use. Other cleaning cloths or wipes notmeeting those requirements may also be suitable for this purpose.6.7 Adhesive Tape
33、, suitable for securing the template(s) tothe surface(s) to be sampled, and for demarcating samplingareas if templates are not used.NOTE 6Masking tape, for example, functions well for these purposes.6.8 Disposable Shoe Covers, optional.7. Procedure7.1 Use one of the following two procedures for coll
34、ectingsettled dust samples from each sampling location. For wide,flat locations, it is recommended to use the template-assistedsampling procedure (see 7.1.1.2(1). For small locations (forexample, window sill, section of a piece of equipment, orportion of a vehicle interior), it will ordinarily be ne
35、cessary touse the confined-area sampling procedure (see 7.1.1.2(2).NOTE 7Metal contamination problems during field sampling can besevere and may affect subsequent wipe sample analysis results. Contami-nation can be minimized through frequent changing of gloves, use of shoecovers (see 6.8), and regul
36、ar cleaning of sampling equipment withcleaning cloths (see 6.6). Use of disposable shoe covers between differentlocations, and removal of them prior to leaving the sampling site orentering vehicles, can be helpful in minimizing inadvertent transfer ofcontaminated dust from one location to another.7.
37、1.1 Sampling Procedure:3Dufay, S.K., and Archuleta, M., “Comparison of Collection Efficiency ofSampling Methods for Removable Beryllium Surface Contamination”, J. Environ.Monit., Vol. 8, Issue 6, pp. 630633 (2006); DOI 10.1039/b601526n.D7296 1227.1.1.1 Don a pair of clean, powderless, plastic gloves
38、 (see6.5 and Note 7).7.1.1.2 Use one of the following three procedures, (1), (2),or (3):(1) Carefully place a clean template on the surface to besampled in a manner that minimizes disturbance of settled dustat the sampling location. Tape the outside edge of the templateto prevent the template from m
39、oving during sample collection.(2) Alternatively, mark the defined area to be sampled withadhesive tape (see 6.7) being careful not to disturb the settleddust, and measure the area to be sampled using the measuringtool (see 6.4).(3) When templates or tape cannot be used or are imprac-tical, the samp
40、ling area may be visually defined based on thesize, shape, geometry, and/or visible landmarks on the surfacebeing sampled or adjacent areas. Templates or rulers used in anon-contact manner can aid in collecting the sample ormeasuring the area sampled.7.1.1.3 Obtain a dry wipe (see 6.2) and, if there
41、 is apossibility for the package containing the wipe to be contami-nated with dust, clean the outside of the package with acleaning cloth (see 6.6).7.1.1.4 Remove the dry wipe from its package, and inspectthe dry wipe to ensure that it is dry and not contaminated withdust or other material. Discard
42、the dry wipe if it is found to bedamp or contaminated, or both.7.1.1.5 Using an open flat hand with the fingers together,place the dry wipe on the surface to be sampled. Wipe theselected surface area, side to side, in an overlapping “S” or “Z”pattern while applying pressure to the fingertips (refer
43、to Figs.1 and 2). Wipe the surface so that the entire selected surfacearea is covered. Perform the wiping procedure using the fingersand not the palm of the hand.7.1.1.6 Repeat 7.1.1.5 using a different type of dry wipematerial (after selecting a different sampling location) if the drywipe originall
44、y used significantly changes shape (for example,rolls up by curling) or tears during the wiping process.NOTE 8Some surfaces (for example, rough surfaces) may causecertain wipes to curl up or otherwise significantly change shape during thewiping process. A type of wipe that maintains its integrity sh
45、ould beselected for each surface sampled.7.1.1.7 Fold the dry wipe in half with the collected dust sidefolded inward and repeat the preceding wiping procedure (see7.1.1.5) within the selected sampling area using an up anddown overlapping “S” or “Z” pattern at right angles to the firstwiping (see Fig
46、. 1, Fig. 2, and Note 9).NOTE 9Dry wipes are folded to envelop the collected dust within thewipe, to avoid loss of the collected dust, and to expose a clean wipesurface for further dust collection from the sampling location. For sampleareas containing large amounts of settled dust, care must be take
47、n duringwiping to capture all of the dust present within the dry wipe.7.1.1.8 Fold the dry wipe in half again with the collecteddust side folded inward and repeat the wiping procedure onemore time, concentrating on collecting settled dust from edgesand corners within the selected surface area (see F
48、ig. 1, Fig. 2,and Note 9).7.1.1.9 Fold the dry wipe again with the collected dust sidefolded inward and insert the wipe into a sample container (see6.3).7.1.1.10 Label the sample container with sufficient informa-tion to uniquely and indelibly identify the sample, and recordthe dimensions (in square
49、 centimetres) of the selected samplingarea (that is, the internal dimensions defined by the template orthe taped area). Discard the gloves.7.2 Collect field blanks at a minimum frequency of 5 % (atleast one field blank for every 20 wipe samples collected). Theminimum number of field blanks to collect for each batch ofdry wipe material used shall be three. Place field blanks insample containers and label these samples in the same fashionas the collected surface dust samples (see 7.1.1.10).7.3 Follow sampling chain of custody procedures to ensuresample traceabilit
