1、Designation: D 5578 04Standard Test Method forDetermination of Ethylene Oxide in Workplace Atmospheres(HBr Derivatization Method)1This standard is issued under the fixed designation D 5578; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev
2、ision, 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 covers a method of collecting andanalyzing samples to determine the amount of eth
3、ylene 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 values stated in SI
4、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 of regulatory
5、limitations prior to use. See Section 9 forspecific safety hazards.2. Referenced Documents2.1 ASTM Standards:2D 1356 Terminology Relating to Sampling and Analysis ofAtmospheresD 3686 Practice for Sampling Atmospheres to Collect Or-ganic Compound Vapors (Activated Charcoal Tube Ad-sorption Method)D 3
6、687 Practice for Analysis of Organic Compound VaporsCollected by the Activated Charcoal Tube AdsorptionMethodE 355 Practice for Gas Chromatography Terms and Rela-tionships2.2 Other Standard:Occupational Safety and Health Administration, U.S. De-partment of Labor, Title 29, Code of Federal Regulation
7、s,Part 1910, Subpart Z, Section 1910.1047.33. Terminology3.1 For definitions of terms used in this test method, refer toTerminology D 1356, and Practice E 355.4. Summary of Test Method4.1 A known volume of air is pumped through a glass tubepacked with carbon molecular sieve, surface area 400 m2/gimp
8、regnated 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 section ha
9、s 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 analyzing
10、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 inthe United
11、 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.1This test method is under the j
12、urisdiction of ASTM Committee D22 onSampling and Analysis of Atmospheres and is the direct responsibility of Subcom-mittee D22.04 on Workplace Atmospheres.Current edition approved October 1, 2004. Published October 2004. Originallyapproved in 1994. Last previous edition approved in 1999 as D 5578 -
13、94(1999)e1.2For 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.3Available from Superintendent of Documents, U.S.
14、Government PrintingOffice, Washington, DC 20402.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2.1 OSHA Permissible Exposure Limit (PEL) 1 ppm,15-min excursion limit 5 ppm (CFR, Part 1910, Subpart Z,Section 1910.1047).35.2.2 ACGIH
15、 Threshold Limit Value (TLV) 1 ppm (1.8mg/m3), suspected human carcinogen.46. Interferences6.1 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 res
16、olved by altering gaschromatographic operating conditions. The identity of sus-pected 2-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
17、/g, HBrsampling tube.7.1.1 Preparation of Collection MediumAdd 20 mL ofHBr (24 %) to 70 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
18、a plug of silanized glasswool into a 10-cm by 6-mm outside diameter (4-mm insidediameter) 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
19、the adsorbent in the backupsection. Hold the backup section in place by firmly inserting 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 andprotect
20、ing worker during sampling.7.1.4 High-Density Polyethylene or Polypropylene Caps,tight-fitting, 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,
21、6-mm inside diameter, forconnecting collection tube to pump. All tubing must bedownstream (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 desor
22、bing solution tosamples.7.5 Syringes, 10, 50, and 100-L syringes, for preparingstandards.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
23、capillary col-umns in accordance with 7.7.2.1 and 7.7.2.2 have been foundsuitable for this 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.
24、53-mm inside diameter fusedsilica capillary column with polyethylene glycol phase.8. Reagents8.1 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 specification
25、s are available.5Other gradesmay be used, provided it is first ascertained that the reagent 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 Deso
26、rbing Solution, 1+1 (v/v) mixture of acetonitrileand toluene.8.5 Sodium Carbonate (Na2CO3).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 inhalat
27、ion and skin contact with all reagents andsolvents.9.3 Use suitable protective holders when 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 D 3686, with the ETO sampling t
28、ube positionedvertically and in line during calibration of the pump.10.1.2 Calibrate the flow rate of the pump at 20 mL/min forTWA sampling 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-bro
29、moethanol stock solution (1 g/L)by adding 57 L of 2-bromoethanol to 100 mL of toluene. Ifrefrigerated, 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 calib
30、ration standards equivalent to4Threshold Limit Values for Chemical Substances and Physical Agents andBiological Exposure Indices, American Conference of Governmental IndustrialHygienists, 6500 Glenway Avenue, Building D-7, Cincinnati, OH 45211-4438.5Reagent Chemicals, American Chemical Society Speci
31、fications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Conven
32、tion, Inc. (USPC), Rockville,MD.D55780420.0, 3.5, 17.4, 34.5, and 67.7 g of ETO per 5 mL of desorbingsolution. 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 c
33、urve by injecting these stan-dards into the GC following the procedure specified in 11.3.5and 11.3.6. 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 solu
34、tions;however, 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
35、.11.1.2 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 sampl
36、ing 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. Immediate
37、ly 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. Treatth
38、e 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 po
39、rtions 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
40、 over-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 o
41、f 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 labe
42、led 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 adsor
43、bent 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 solv
44、ent flush technique as described in PracticeD 3687. 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
45、.0 and 8.0 min, respectively.11.3.6.1 Gas Chromatographic Operating ConditionsColumn temperature, 155C; injection port and detector tem-peratures, 240C; carrier gas (5 % methane/argon) flow rate, 30mL/min (packed column) or 20 cm/s (capillary column).11.3.6.2 Determine the peak height or peak area o
46、f the2-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
47、the 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
48、),24.47 = molar volume of an ideal gas, L/mole, at 25C 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 conta
49、mi-nated (see Practice D 3687).6NIOSH Manual of Analytical Methods, Cincinnati, OH 45226.D557804313. 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 beingdetermined.13.1.1 The values shown in Table 1 are averages of sixreplicates obtained for each concentration of ETO generated ina 6920L static chamber. They take into account adsorption/desorption efficiency and the
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