1、Designation: D7202 15Standard Test Method forDetermination of Beryllium in the Workplace by Extractionand Optical Fluorescence Detection1This standard is issued under the fixed designation D7202; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、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 test method is intended for use in the determinationof beryllium by sampling workplace a
3、ir and surface dust.1.2 This test method assumes that air and surface samplesare collected using appropriate and applicable ASTM Interna-tional standard practices for sampling of workplace air andsurface dust. These samples are typically collected using airfilter sampling, vacuum sampling or wiping
4、techniques. SeeGuide E1370 for guidance on air sampling strategies, andGuide D7659 for guidance on selection of surface samplingtechniques.1.3 Determination of beryllium in soil is not within thescope of this test method. See Test Method D7458 fordetermination of beryllium in soil samples.1.4 This t
5、est method includes a procedure for extraction(dissolution) of beryllium in weakly acidic medium (pH of 1 %aqueous ammonium bifluoride is 4.8), followed by fieldanalysis of aliquots of the extract solution using a beryllium-specific-optically fluorescent dye.1.5 The procedure is suitable for on-site
6、 use in the field foroccupational and environmental hygiene monitoring purposes.The method is also applicable for use in fixed-site laboratories.1.6 No detailed operating instructions are provided becauseof differences among various makes and models of suitablefluorometric instruments. Instead, the
7、analyst shall follow theinstructions provided by the manufacturer of the particularinstrument. This test method does not address comparativeaccuracy of different devices or the precision between instru-ments of the same make and model.1.7 The values stated in SI units are to be regarded asstandard.
8、No other units of measurement are included in thisstandard.1.8 This test method contains notes that are explanatory andnot part of mandatory requirements of the standard.1.9 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility
9、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:2D1193 Specification for Reagent WaterD1356 Terminology Relating to Sampling and Analysis ofAtmospheres
10、D4840 Guide for Sample Chain-of-Custody ProceduresD5337 Practice for Flow Rate Adjustment of Personal Sam-pling PumpsD6966 Practice for Collection of Settled Dust SamplesUsing Wipe Sampling Methods for Subsequent Determi-nation of MetalsD7035 Test Method for Determination of Metals and Met-alloids i
11、n Airborne Particulate Matter by InductivelyCoupled Plasma Atomic Emission Spectrometry (ICP-AES)D7144 Practice for Collection of Surface Dust by Micro-vacuum Sampling for Subsequent Metals DeterminationD7296 Practice for Collection of Settled Dust SamplesUsing Dry Wipe Sampling Methods for Subseque
12、nt De-termination of Beryllium and CompoundsD7458 Test Method for Determination of Beryllium in Soil,Rock, Sediment, and Fly Ash Using Ammonium Bifluo-ride Extraction and Fluorescence DetectionD7659 Guide for Strategies for Surface Sampling of Metalsand Metalloids for Worker ProtectionD7707 Specific
13、ation for Wipe Sampling Materials for Beryl-lium in Surface DustE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method1This test method is under the jurisdiction of ASTM Committee D22 o
14、n AirQuality and is the direct responsibility of Subcommittee D22.04 on Workplace AirQuality.Current edition approved Oct. 1, 2015. Published October 2015. Originallyapproved in 2005. Last previous edition approved in 2014 as D7202 141. DOI:10.1520/D7202-15.2For referenced ASTM standards, visit the
15、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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. Uni
16、ted States1E882 Guide for Accountability and Quality Control in theChemical Analysis LaboratoryE1370 Guide for Air Sampling Strategies for Worker andWorkplace ProtectionE1792 Specification for Wipe Sampling Materials for Leadin Surface Dust3. Terminology3.1 DefinitionsFor definitions of terms not ap
17、pearing here,see Terminology D1356.3.2 Definitions of Terms Specific to This Standard:3.2.1 wipe, na disposable towelette that is moistened witha wetting agent such as water. E1792; D69663.2.1.1 DiscussionThese towelettes are used for collectingsamples of dust, potentially containing beryllium, from
18、 sur-faces.3.2.2 wipe sample, nsample collected by wiping a repre-sentative surface of known area, as determined by PracticeD6966, or equivalent method, with an acceptable wipe materialas defined in Specification D7707.4. Summary of Test Method4.1 Particles potentially containing beryllium from work
19、-place air or surfaces, or both, are collected in the field usingprocedures described in ASTM International standards. Toextract (or dissolve) beryllium in the collected samples, themedia in or on which the samples are collected (that is, airsample, vacuum sample or wipe) are treated using an acidic
20、extraction solution containing dilute ammonium bifluoride,NH4HF2(1).3The presence of active fluoride ions (HF bydissociation of ammonium bifluoride in acidic medium) en-ables dissolution of refractory materials such as “high-fired”beryllium oxide. The extraction solution produced from eachsample is
21、then filtered and an aliquot of this extract is added toa pH-adjusted detection solution which contains a beryllium-specific optical fluorescence reagent (1, 2). The fluorescenceexhibited by this final solution is then measured on a calibratedfluorometer to quantify the amount of beryllium in the sa
22、mple(3).5. Significance and Use5.1 Exposure to beryllium can cause a potentially fataldisease, and occupational exposure limits for beryllium in airand on surfaces have been established to reduce exposure risksto potentially affected workers (4, 5). Sampling and analyticalmethods for beryllium are n
23、eeded in order to meet thechallenges relating to exposure assessment and risk reduction.Sampling and analysis methods, such as the procedure de-scribed in this test method, are desired in order to facilitateon-site and fixed-site laboratory measurement of trace beryl-lium. Beryllium analysis results
24、 can then be used as a basis forexposure assessment and protection of human health.6. Interferences6.1 This test method is highly specific for beryllium. Othersolvated metal ions are either bound by ethylenediaminetet-raacetic acid (EDTA) in the detection solution, or they precipi-tate out due to th
25、e high alkalinity of the detection solution (1).In case the sample is suspected of having fluorescent organiccontaminants that are suspected to be present, then theirpresence can be checked and removed (6).NOTE 1If the samples are suspected of having a contaminant thatfluoresces and has excitation a
26、nd emission spectra that overlap with thatof the signal produced by the fluorescent dye bound to beryllium, then thiscontaminant needs to be removed. The presence of such a contaminant canbe verified by subjecting the filtered sample to fluorescence excitationafter the extraction step (without addin
27、g the fluorescent dye). If afluorescence signal is detected, then that signal is ascribed to the presenceof a fluorescent contaminant. To remove the contaminant, high-purityactivated charcoal is added to the beryllium extraction solution and theextraction procedure is carried out at elevated tempera
28、ture (80 to 90C forat least 45 minutes). If the beryllium extraction procedure has alreadybeen performed, then after the addition of activated charcoal, theextraction process is repeated at the elevated temperature. The solution isfiltered to remove the activated charcoal before making the measureme
29、ntsolution. The measurement solution is made by the addition of thefluorescent dye solution to an aliquot of the extraction solution. Details ofthis process have been published (6).6.2 If iron is present in high excess in the sample (typicallymore than 20 M), the resulting measurement solution mayap
30、pear golden-yellow. In this case the solution should be leftfor an hour or more for the iron to precipitate. The solutionshould then be re-filtered using the same procedure as forfiltering the dissolution solution (after the dissolution step),prior to fluorescence measurement.7. Apparatus7.1 Samplin
31、g Equipment:7.1.1 Air SamplingUse air samplers and filters for collect-ing personal air samples as described in Test Method D7035.7.1.2 Wipe SamplingUse wipe sampling apparatus forcollecting surface dust samples as described in Practice D6966(or Practice D7296 in special cases), using wipes meeting
32、thespecifications described in Specification D7707.7.1.3 Vacuum SamplingIf wipe sampling is not advisablefor surface sample collection, use vacuum sampling apparatusfor collecting surface dust samples as described in PracticeD7144.7.2 Instrumentation:7.2.1 Ultraviolet/Visible (UV/Vis) Fluorometer, w
33、ith irradi-ance excitation lamp (excitation = 380 nm) and time-integrating visible detector (400700 nm, max 475 nm).7.2.2 Mechanical Agitator or Heating Source, shaker, rota-tor or ultrasonic bath; or heat block, oven or heating bath.NOTE 2For routine samples, a shaker, rotator, or ultrasonic bath i
34、sadequate. To achieve higher recoveries from beryllium oxide (especially“high-fired” BeO), a heat block, oven or heating bath is required.7.3 Laboratory Supplies:7.3.1 Centrifuge tubes, plastic, 15-mL (plus 50-mL, ifnecessary).7.3.2 Syringe filters, 0.2 to 0.45-m nylon, polyethersulfoneor hydrophili
35、c polypropylene, 13- or 25-mm diameter, inplastic housings.3The boldface numbers in parentheses refer to a list of references at the end ofthis standard.D7202 1527.3.3 Syringes, plastic, 5-mL or 10-mL.7.3.4 Pipetters, mechanical, of assorted sizes as needed.7.3.5 Pipet tips, plastic, disposable, of
36、assorted sizes asneeded.7.3.6 Fluorescence cuvettes, disposable, low fluorescence,10-mm path length, transparent to UV/Vis radiation.7.3.7 Labware, plastic (for example, beakers, flasks, gradu-ated cylinders, etc.), of assorted sizes as needed.7.3.8 Forceps, plastic or plastic-coated.7.3.9 Personal
37、protective wear, for example, respirators,masks, gloves, lab coats, safety eyewear, etc., as needed.7.3.10 Thermometer, to at least 100C.7.3.11 Other general laboratory apparatus, as needed.7.4 Reagents:7.4.1 WaterUnless otherwise indicated, references to wa-ter shall be understood to mean reagent a
38、s defined by Type I ofSpecification D1193 (ASTM Type I Water: minimum resis-tance of 18 M-cm or equivalent)7.4.2 Calibration Stock Solution1000 ppm beryllium indilute nitric acid or equivalent.7.4.3 Ethylenediaminetetraacetic acid (EDTA) disodiumsalt dihydrate.7.4.4 L-lysine monohydrochloride.7.4.5
39、10-hydroxybenzohquinoline-7-sulfonate (10-HBQS).7.4.6 Sodium hydroxide.7.4.7 Extraction (or Dissolution) Solution1 % ammoniumbifluoride (NH4HF2) solution (aqueous) for dissolution ofberyllium in collected particulate matter. (WarningAmmonium bifluoride will etch glass, so it is essential that allNH4
40、HF2solutions be contained in plastic labware.)7.4.8 Detection Solution63.4 M 10-hydroxybenzohquinoline-7-sulfonate (10-HBQS) / 2.5 mMethylenediaminetetraacetic acid (EDTA)/50.8 mM lysinemonohydrochloride (pH adjusted to 12.8 with NaOH): Theaqueous detection reagent is prepared by the addition of 12.
41、5mL of 10.7 mM ethylenediaminetetraacetic acid (EDTA)disodium salt dihydrate and 25 mL of 107 mM L-lysinemonohydrochloride to 3 mL of 1.1 mM 10-hydroxybenzohquinoline-7-sulfonate (10-HBQS). The pH isadjusted to 12.85 with addition of sodium hydroxide and wateradded to a total of 50 mL (1-3). An alte
42、rnative preparation ofdye solution without lysine may be made by adding 1.104 g ofEDTA and 64 moles of the 10-HBQS dye in 900 ml of water.After a clear solution is obtained, 114.5 ml of 2.5 N NaOH isadded and mixed to obtain the final dye solution. The pH of thedye solution is 13.2. The dye solution
43、 without lysine may beused for all analytical purposes and also provides superiordetection limits.NOTE 3For on-site analysis, it is recommended that the extraction anddetection solutions be prepared in a fixed-site laboratory or other suchcontrolled environment prior to transport to the field.8. Pro
44、cedure8.1 Sampling:8.1.1 Air SamplesCollect workplace air samples for be-ryllium in accordance with Test Method D7035, using personalsampling pumps calibrated in accordance with Practice D5337.8.1.2 Wipe SamplesCollect surface wipe samples for be-ryllium in accordance with Practices D6966 and D7296
45、usingwipe materials that comply with Specification D7707.NOTE 4Practice D7296 should only be used when wetted wipesampling is not physically feasible (for example, if the surface to be wipedwould be compromised by use of wetted wipes). Otherwise, PracticeD6966 should be used.8.1.3 Vacuum SamplesIf w
46、ipe sampling is inadvisable forsurface dust sampling, collect surface vacuum samples forberyllium in accordance with Practice D7144.8.1.4 Sample TransportIf applicable (that is, if samplesare transported to a different location prior to sample prepara-tion and analysis), follow sampling chain-of-cus
47、tody proce-dures to document sample traceability. Ensure that the docu-mentation that accompanies the samples is suitable for a chainof custody to be established in accordance with Guide D4840.8.2 Sample PreparationWear appropriate personal protec-tion during sample preparation and analysis activiti
48、es. Performsample preparation and analysis in a clean area that is wellremoved from any possible beryllium contamination.8.2.1 Extraction of Air Filter or Vacuum Samples:8.2.1.1 Don clean gloves and open the samplers. Use eithertechnique (1)or(2) to perform sample extraction on eachcollected sample:
49、(1) Using forceps, remove the filter from the cassette andplace it into 15-mL centrifuge tube. The interior of the cassetteshall be rinsed with extraction solution or wiped with anotherclean filter, and included in the centrifuge tube. For eachvacuum sample, quantitatively transfer all loose dust into thecentrifuge tube before removing the filter and then rinsing orwiping the inside walls of the sampler.(2) Alternatively, the extraction shall be carried out directlywithin the sampling cassette (see Test Method D7035).8.2.1.2 Pipet 5 mL of 1 %
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