1、Designation: D5578 04 (Reapproved 2010)Standard Test Method forDetermination of Ethylene Oxide in Workplace Atmospheres(HBr Derivatization Method)1This standard is issued under the fixed designation D5578; the number immediately following the designation indicates the year oforiginal adoption or, in
2、 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 test method covers a method of collecting andanalyzing samples to determine th
3、e amount of ethylene oxide(ETO) present in workplace atmospheres.1.2 This test method can be used to provide a time-weightedaverage (TWA) over the concentration range from 0.2 to 4 ppm(v).1.3 This test method can be used to determine 15-minexcursions (STEL) ranging from 1 to 25 ppm (v).1.4 The value
4、s stated in SI units are to be regarded as thestandard.1.5 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 appro-priate safety and health practices and determine the applica-bility
5、 of regulatory limitations prior to use. See Section 9 forspecific safety hazards.2. Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD3686 Practice for Sampling Atmospheres to Collect Or-ganic Compound Vapors (Activated Charcoal Tube Ad-sorpti
6、on Method)D3687 Practice for Analysis of Organic Compound VaporsCollected by the Activated Charcoal Tube AdsorptionMethodE355 Practice for Gas Chromatography Terms and Rela-tionships2.2 Other Standard:3Occupational Safety and Health Administration, U.S. De-partment of Labor, Title 29, Code of Federa
7、l Regulations,Part 1910, Subpart Z, Section 1910.1047.3. Terminology3.1 For definitions of terms used in this test method, refer toTerminology D1356, and Practice E355.4. Summary of Test Method4.1 A known volume of air is pumped through a glass tubepacked with carbon molecular sieve, surface area 40
8、0 m2/gimpregnated with hydrogen bromide (HBr) where ETO isadsorbed and converted to 2-bromoethanol.4.2 The tube contains two reactive sections for samplecollection. The backup section collects vapors that passthrough the front section and is used to determine if thecollection capacity of the front s
9、ection has been exceeded.4.3 The resultant derivative, 2-bromoethanol, is desorbedwith a mixture of acetonitrile/toluene and analyzed using a gaschromatograph equipped with an electron capture detector.4.4 Desorption efficiency is determined by spiking tubeswith known amounts of 2-bromoethanol and a
10、nalyzing with thesame procedure used for air samples.4.5 Quantitation is achieved by comparing peak areas fromsample solutions with areas from standard solutions.5. Significance and Use5.1 Ethylene oxide is a major industrial chemical withproduction volume ranked in the top 25 chemicals produced int
11、he United States. It is used in the manufacture of a greatvariety of products as well as being a sterilizing agent andfumigant.5.2 This test method provides a means of determiningexposure levels of ETO in the working environment at thepresently recommended exposure guidelines.5.2.1 OSHA Permissible
12、Exposure Limit (PEL) 1 ppm,15-min excursion limit 5 ppm (CFR, Part 1910, Subpart Z,Section 1910.1047).35.2.2 ACGIH Threshold Limit Value (TLV) 1 ppm (1.8mg/m3), suspected human carcinogen.41This test method is under the jurisdiction of ASTM Committee D22 on AirQuality and is the direct responsibilit
13、y of Subcommittee D22.04 on Workplace AirQuality.Current edition approved April 1, 2010. Published June 2010. Originallyapproved in 1994. Last previous edition approved in 2004 as D5578 - 04. DOI:10.1520/D5578-04R10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM
14、 Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Superintendent of Documents, U.S. Government PrintingOffice, Washington, DC 20402.4Threshold Limit Values for Chemical Substances
15、 and Physical Agents andBiological Exposure Indices, American Conference of Governmental IndustrialHygienists, 6500 Glenway Avenue, Building D-7, Cincinnati, OH 45211-4438.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Interferen
16、ces6.1 Derivatives and other compounds that have identical ornearly the same GC column retention time as 2-bromoethanolduring the gas chromatographic analysis will interfere.6.2 Interferences can sometimes be resolved by altering gaschromatographic operating conditions. The identity of sus-pected 2-
17、bromoethanol, or the presence of 2-bromoethanolmasked by a chromatographic interference, or both, can beverified by gas chromatography/mass spectrometry.7. Apparatus7.1 Carbon Molecular Sieve, surface area 400 m2/g, HBrsampling tube.7.1.1 Preparation of Collection MediumAdd 20 mL ofHBr (24 %) to 70
18、g of carbon molecular sieve, surface area 400m2/g, in a glass jar. Cap the jar and mix the contents thoroughlyfor 5 min by rotating.Allow to equilibrate and dry overnight orfor 12 h.7.1.2 Tube PreparationInsert a plug of silanized glasswool into a 10-cm by 6-mm outside diameter (4-mm insidediameter)
19、 glass tube. Pack the front section of the tube with400 mg of the reactive adsorbent (7.1.1), using gentle tappingor vibration to promote uniform packing. Insert another plug ofsilanized wool and pack 200 mg of the adsorbent in the backupsection. Hold the backup section in place by firmly inserting
20、anadditional glass wool plug. The tubes may be flame-sealed orsealed with polyethylene caps. Provide a numerical identifica-tion for each lot of tubes.7.1.3 Tube Holder, capable of preventing breakage andprotecting worker during sampling.7.1.4 High-Density Polyethylene or Polypropylene Caps,tight-fi
21、tting, for resealing used tubes.7.2 Pump and Tubing:7.2.1 Sampling Pumps, having stable low flow rates(610 % of set flow rate) within the range from 20 to 100mL/min for up to 8 h.7.2.2 Rubber or Plastic Tubing, 6-mm inside diameter, forconnecting collection tube to pump. All tubing must bedownstream
22、 (between tube and pump) of collection tube toprevent contamination or loss of sample.7.3 Vials, glass with PTFE-lined caps, 10 mL, for desorbingsamples and storing standards.7.4 Pipettes, 5 mL, for adding desorbing solution tosamples.7.5 Syringes, 10, 50, and 100-L syringes, for preparingstandards.
23、7.6 Gas-Tight Syringe, 2 L, with low dead-volume needle.7.7 Gas Chromatograph (GC):7.7.1 Gas Chromatograph, with an electron capture detectorand a suitable readout device.7.7.2 Chromatographic Column, packed or capillary col-umns in accordance with 7.7.2.1 and 7.7.2.2 have been foundsuitable for thi
24、s analysis.7.7.2.1 Packed, 3.7 m by 3 mm (12 ft by18 in.), stainlesssteel, packed with 10 % diethylene glycol succinate on diato-maceous earth, flux-calcined, silanized, 80/100 mesh.7.7.2.2 Capillary, 30-m by 0.53-mm inside diameter fusedsilica capillary column with polyethylene glycol phase.8. Reag
25、ents8.1 Purity of ReagentsUnless otherwise indicated, it isintended that all reagents conform to the specifications of theCommittee on Analytical Reagents of the American ChemicalSociety where such specifications are available.5Other gradesmay be used, provided it is first ascertained that the reage
26、nt isof sufficiently high purity to permit its use without lesseningthe accuracy of the determination.8.2 Acetonitrile, pesticide grade.8.3 2-Bromoethanol, commercially available at 98 % purityor better.8.4 Desorbing Solution, 1+1 (v/v) mixture of acetonitrileand toluene.8.5 Sodium Carbonate (Na2CO3
27、).8.6 Toluene, pesticide grade.9. Hazards9.1 Minimize exposure to all reagents and solvents byperforming all sample and standard preparations as well as tubedesorption in a well-ventilated hood.9.2 Avoid inhalation and skin contact with all reagents andsolvents.9.3 Use suitable protective holders wh
28、en collecting samplesand handle used tubes carefully to prevent injury.10. Calibration10.1 Sample Pump Calibration:10.1.1 Calibrate the sample pump flow in accordance withPractice D3686, with the ETO sampling tube positionedvertically and in line during calibration of the pump.10.1.2 Calibrate the f
29、low rate of the pump at 20 mL/min forTWAsampling and 100 mL/min for STEL sampling dependingon the duration of the sample and the volume of sampleneeded.10.2 Gas Chromatograph Calibration:10.2.1 Prepare a 2-bromoethanol stock solution (1 g/L)by adding 57 L of 2-bromoethanol to 100 mL of toluene. Ifre
30、frigerated, this solution is stable for at least one month.10.2.2 To a series of five 10-mL vials containing 5.0 mL ofdesorbing solution, add 0.0, 10, 50, 100, and 200 L of stocksolution, thus, providing calibration standards equivalent to0.0, 3.5, 17.4, 34.5, and 67.7 g of ETO per 5 mL of desorbing
31、solution. These values take into account volume changescaused by the addition of stock solution.10.2.3 The 0.0-g standard described in 10.2.2 constitutes areagent blank.10.2.4 Prepare a calibration curve by injecting these stan-dards into the GC following the procedure specified in 11.3.5and 11.3.6.
32、 Plot the peak area (or height) versus micrograms ofETO per 5 mL of desorbing solution.10.2.5 To cover a broader ETO concentration range, prepareadditional standards with the stock and desorbing solutions;5Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washing
33、ton, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.D5578 04 (20
34、10)2however, exercise care by staying within the linear dynamicrange of the electron capture detector.11. Procedure11.1 Sample Collection:11.1.1 Immediately before sampling, break off the ends ofthe sampling tube (if flame sealed) or remove end caps tocreate an opening of at least 2 mm in diameter.1
35、1.1.2 Attach a collection tube to a calibrated samplingpump using a section of plastic tubing, with the backup sectionnearest the pump.11.1.3 Place the tube vertically in the tube holder as near tothe breathing zone as possible.11.1.4 Activate the sampling pump that has been calibratedat the samplin
36、g site with the sampling tube in-line for the flowrate desired (20 mL/min for 8 h; or 100 mL/min for 15 min).11.1.5 Record the time, flow rate, barometric pressure, andtemperature when the pump is started.11.1.6 When sampling is completed, check the flow ratebefore deactivating the pump. Immediately
37、 record the time,temperature, and barometric pressure again.11.1.7 Disconnect the sample tube and cap the ends withpolyethylene caps. Label the tube with sample identification.11.1.8 Include at least one blank sampling tube with every10 to 15 samples, or for each operation or field survey. Treatthe
38、field blank the same as air samples with the exception thatno air is drawn through the blank tube. The field blank must befrom the same tube lot as the air samples.11.2 Desorption Effciency:11.2.1 Determine the desorption efficiency on the same lotof tubes as the air samples.11.2.2 Place 400-mg port
39、ions of collection medium (7.1.1)in each of several 10-mL vials.11.2.3 Add appropriate amounts of 2-bromoethanol stocksolution (10.2.1) directly onto the adsorbent prepared in 11.2.2,that correspond to the approximate levels of ETO expected inair samples. Allow the spiked adsorbents to equilibrate o
40、ver-night (or 12 h) at room temperature.11.2.4 Analyze replicates of each concentration level alongwith 400mg adsorbent tube blanks using the procedureindicated in 11.3.5-11.3.6, inclusively. Calibrate the gas chro-matograph using mass of 2-bromoethanol in calibration stan-dards (10.2.2) instead of
41、ETO equivalent.11.2.5 Calculate the desorption efficiency (DE) for eachamount of 2-bromoethanol as follows:DE 5Wr2 BWa(1)where:Wr= average mass recovered, g,B = blank, g, andWa= mass added, g.11.3 Analysis:11.3.1 Add 100 mg of Na2CO3and 5.0 mL of desorbingsolution to each of the appropriately labele
42、d vials that indicatethe tube numbers and front or backup section.11.3.2 Score and break tubes just above the front glass woolplug, remove plug, and slowly add front portion of adsorbent tothe appropriate vial. Seal the vial.11.3.3 Remove the glass wool separator and add the backupsection of adsorbe
43、nt to the proper vial. Make certain adsorbentparticles are not retained on the glass wool plugs and separatorbefore discarding.11.3.4 Desorb for 30 min at room temperature, shaking thevial occasionally during this period.11.3.5 Quantitatively inject 2 L of sample solution into theGC using the solven
44、t flush technique as described in PracticeD3687. Alternatively, samples may be injected using anautomated injection system.11.3.6 Complete the GC analysis following the chromato-graphic conditions described in 11.3.6.1. The approximateETO retention time and total chromatographic analysis time is4.0
45、and 8.0 min, respectively.11.3.6.1 Gas Chromatographic Operating ConditionsColumn temperature, 155 C; injection port and detectortemperatures, 240 C; carrier gas (5 % methane/argon) flowrate, 30 mL/min (packed column) or 20 cm/s (capillarycolumn).11.3.6.2 Determine the peak height or peak area of th
46、e2-bromoethanol.12. Calculation12.1 Correct samples for ETO found in the sampling tubeblank (10.2.3).12.2 Determine the amount (g) of ethylene oxide in thefront and backup sections of the sample tube using thecalibration curve generated in 10.2.4. If the backup sectioncontains more than 10 % of the
47、amount of ethylene oxidecontained in the front section, report breakthrough and possiblesample loss.612.3 Calculate the concentration of ETO in the air samplesas follows:Ethylene Oxide, ppm by volume 5W 3 24.47DE 3 L 3 44.05(2)where:W = micrograms of ETO in sample (sum of front andbackup section),24
48、.47 = molar volume of an ideal gas, L/mole, at 25 C and101.3 kPa (760 mm Hg),DE = desorption efficiency,L = volume of air sampled, L, and44.05 = molecular weight of ethylene oxide, g/mole.12.4 If a field blank shows contamination, the samplescollected during the survey must be assumed to be contami-
49、nated (see Practice D3687).6NIOSH Manual of Analytical Methods, Cincinnati, OH 45226.TABLE 1 Precision and Accuracy of Chamber ConcentrationsTheoretical ETOConcentration, ppmAverage Recovery, %Relative StandardDeviation, %0.5 111.6 1.61.0 100.6 2.05.0 100.8 3.610.0 101.8 5.620.0 102.1 2.9D5578 04 (2010)313. Precision and Bias713.1 PrecisionBased on limited information from onelaboratory, the repeatability standard deviations and the 95 %repeatability limits are approximately 69.3 %, as illustrated inTable 1. The reproducibility of this test method is beingdet
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