Document LKQOxKzrnmj9vrRYG5jb8ezjb

T05-6 10.2 Prior to sample collection the entire assembly (including empty sample impingers) is installed and the flow rate checked at a value near the desired rate. In general flow rates of 100-1000 ml/minute are useful. Flow rates greater than vlOOO mL/minute should not be used because impinger collection efficiency may decrease. Generally calibration is accomplished using a soap bubble flow meter orv calibraled wet test meter connected to the flow exit, assuming the entire system is sealed. ASTM Method D3686 describes an appropriate calibration scheme not requiring a sealed flow system downstream of the pumo. 10.3 Ideally a dry gas meter is included in the system to record total flow. If a dry gas meter is not available the operator must measure and record the sampling flow rate at the beginning and end of the sampling period to determine sample volume. If the sampling period exceeds two hours the flow rate should be measured at intermediate points during the sampling period. Ideally a rotameter should be included to allow observation of the flow rate without interruption of the sampling process. 10.4 To collect an air sample two clean midget impingers are loaded with 10 ml of purified DNPH reagent and 10 mL of isooctane. The impingers are connected in series to the sampling system and sample flow Is started. The follow ing parameters are recorded on the data sheet (see Figure 3 for an example): date, sampling location, time, ambient temperature, barometric pressure (if available), relative humidity (if available), dry gas meter reading (if appro 10.5 priate), flow rate, rotometer setting, DNPH reagent batch number, and dry gas meter and pump identification numbers. The sampler is allowed to operate for the desired period, with periodic recording of the variables listed above. The total flow should not exceed *v80 liters. The operator must ensure that at least 2-3 ml of isooctane remains in the first impinger at the end of the sampling interval (i.e. for high ambient temperatures lower sampling volumes may be required). BFG15431 1574127 T05-7 10.6 At the end of the sampling period the parameters listed in 10.4 are recorded and the sample flow is stopped. If a dry gas meter is not used the flow rate must be checked at the end of the sampling interval. If the flow rate at the beginning and end of the sampling period differ by more than 152 the sample should be marked as suspect. 10.7 Immediately after sampling the impingers are removed from the sampling system. The contents of the first impinger are emptied^i^to a clean 50 ml glass vial having a teflonlined screw cap. The first impinger is then rinsed with the contents of the second (backup) impinger and the rinse solution is added to the vial. The vial is then capped, sealed with teflon tape and placed in a friction top can containing 1-2 inches of granular charcoal. The samples are stored in the can, refrigerated until analysis. 10.8 If a dry gas meter or equivalent total flow indicator is not used the average sample flow rate must be calculated according to the following equation: where Q ------ 1---------i--------------- S-- AN 10.9 * Average flow rate in mL/minute. Qj( Q2...Qn* Flow rates determined at the * beginning, end, and Intermediate points during sampling. N * Number of points averaged. The total flow is then calculated using the following equation: (YTi >qA V m * -------2 1000 Vm* Total volume sampled In liters at measured temperature and pressure Tj Stop time Tj * Start time (Tg-T-j given in minutes) Z1574-12S BFG15432 T05-8 11. Sample Analysis 11.1 Sample Preparation 11.1.1 11.1.2 11.1.3 11.1.4 The samples are returned to the laboratory in 50 mL screw-capped glass vials. To recover the DNPH derivatives the following procedure is em- pjo^ed. , The vials are shaken in a horizontal position on a reciprocating shaker for 10 minutes. The vials are then removed from the shaker and the isooctane layer is removed and placed in a second clean 50 mL screw-capped glass vial using a disposable pipette. The remaining aqueous layer is extracted with 10 mL of 70/30 (V/V) hexane/methylene chloride in the same manner as described in 11.1.2. The organic layer is removed and combined with the isooctane extract. The combined organic extracts are then concentrated to dryness at 40C under a steam of pure nitrogen. When the sample just reaches dryness the vial is removed from the nitrogen stream and a measured volume (2-5 mL) of methanol is added to the vial. The vial Is tightly capped and stored refrigerated until analysis. 11.2 HPLC Analysis 11.2.1 11.2.2 The instrument is assembled and calibrated as described in Section 12. Prior to each analysis the detector baseline is checked to ensure stable operation. A 5-25 uL aliquot of the sample, dissolved in ^ methanol,Is drawn into a clean HPLC injection syringe. ^ The sample Injection loop is loaded and an Injection ^ is made. The data system. If available, is activated ^ simultaneously with the injection and the point of injection is marked on the stripchart recorder. Jsj ^ BFG15433 11.2.3 11.2.4 11.2.5 11.2.6 After approximately one minute, the injection valve is returned to "load" position and the syringe and valve are flushed with methanol in preparation for the next sample analysis. After elution of the last component of interest the acquisition is terminated and the component concen trations are calculated as described in Section 13. After a stable baseline is achieved the system can be used for further sample analyses as described above. if'the concentration of a component exceeds the linear range of the instrument the sample should be diluted with methanol, or a smaller volume can be injected onto the HPLC. HPLC Assembly and Calibration 12.1 The HPLC system is assembled as shown in Figure 3. The typical chromatographic performance and operating para meters are shown in Figure 4. 12.2 Mobile phase is prepared by mixing 800 mL of methanol and 200 mL of reagent water. This mixture is filtered through a 0.22 um polyester membrane filter in an all glass and teflon suction filtration apparatus. The filtered mobile phase is degassed by purging with helium gas for 10-15 minutes (v 100 mL/minute) or by heating to n.60C for 5-10 minutes in an Erlenmeyer flask covered with a watch glass. A constant back pressure restrictor (<\, 50 psi) or short length (6-12 inches) of 0.01 inch I.D. teflon tubing should be placed after the detector to further eliminate mobile phase outgassing. 12.3 The mobile phase is placed in the HPLC solvent reservoir and the pump flow is set at 1 mL/minute and allowed to pump for 20-30 minutes prior to the first analysis. The detector is switched on at least 30 minutes prior to the first analysis and the detector output is displayed on a stripchart recorder or similar output device at a sensitivity of .008 21574130 BFG15434 T05-1Q absorbance units full scale (AUFS). Once a stable baseline is achieved the system is ready for calibration. 12.4 Calibration standards are prepared in methanol from the solid DNPH derivatives. Individual stock solutions of v 100 mg/l are prepared by dissolving 10 mg of the solid derivative in 100 ml of methanol. These individual solutions are used to prepare calibration standards containing all of the derivatives of interest at concentrations (of 0.1 - 10 mq/L^) which spans th^ concentration of interest for most ambient air work. 12.5 All calibration runs are performed as described for sample analyses in Section 11. Before initial use the operator should inject a series of calibration standards (at least three levels) spanning the concentration range of interest. Using the UV detector, a linear response range of approximately 0.1 to 10 mg/L should be achieved, for n. 10 ul injection volumes. Linear response is indicated where a correlation coefficient of a least 0.999 for a linear least squares fit of the-data (concentration versus area response) is obtained. * 12.6 Once linear response has been documented an intermediate concentration standard near the anticipated levels for each component, but at least 10 times the detection limit, should be chosen for daily calibration. The response for the various DNPH components should be within 10S day to day. If greater variability is observed more frequent calibration may be required to ensure that valid results are obtained. 12.7 The response for each component in the daily calibration standard is used to calculate a response factor according to the following equation: Cc XVI RF 3 J I 1 BFG15435 cn DC I-* where T05-11 RFc * response factor for the component of interest in nanograms injected/response unit (usually area counts). C * concentration of component in the daily calibration standard (mg/L). Vj = volume of calibration standard injected (jL). R * response for component of interest in v calibration standard (area counts). 13. Calculations 13.1 The volume of air sampled Is often reported uncorrected for atmospheric conditions (i.e. under ambient conditions). However, the value can be adjusted to standard conditions (25C and 760 nm pressure) using the following equation: where 298 x------------ 760 273 + TA * Vs * total sample volume at 25*C and 760 mm Hg pressure (liters). Vm * total sample volume under ambient conditions (liters). Calculated in 10.9 or from dry gas meter reading. Pa ambient pressure (ninHg). Ta ambient temperature (#C). 13.2 The concentration of each aldehyde (as the ONPH derivative is calculated for each sample using the following equation: Z 8 T U .S JZ BFG15436 T05-12 Wa. = RFc,, X Rd. X where * total quantity of derivative in the sample (ig) RFc = response factor calculated in 12.7 \ iRd. s response for component in sample extract (area counts or other response units). = final volume of sample extract (mL). Vj * volume of extract injected onto the HPLC system (uL). 13.3 The concentration of aldehyde in the original sample is calculated from the following equation: where X X 1000 Sn (r Vs ) MWd * concentration of aldehyde in the original sample (ng/L). or Vs are as specified in Section 13.1. MWa and MWd are the molecular weights (g/mole) of the aldehyde and its corresponding DNPH derivative, respectively. 13.4 The aldehyde concentrations can be converted to ppbv using the following equation: 24.4 C.(ppbv) C.(ng/L) X ------- where Cft(ng/L) is calculated using Vs. BFG1543J N U\ CD 0> .m .......... .... ................ ....... T05-13 14. Performance Criteria and Quality Assurance This section summarizes the quality assurance (QA) measures and provides guidance concerning performance criteria which should be achieved within each laboratory. 14.1 Standard Operating Procedures (SOPs). 14.1.1 14.1.2 Each user should generate SOPs describing the fpl^lowing.activities as accomplished in their laboratory: 1) assembly, calibration and operation of the sampling system, 2) preparation, purification, storage and handling of DNPH reagent and samples, 3} assembly, calibration and operation of the HPLC system, and 4) all aspects of data recording and processing. SOPs should provide specific stepwise instructions and should be readily available to, and understood by, the laboratory personnel conducting the work. 14.2 HPLC System Performance 14.2.1 14.2.2 The general appearance of the HPLC chromatograph should be similar to that shown in Figure 4. The HPLC system efficiency and peak asymmetry factor should be determined in the following manner. A solution of the formaldehyde ONPH derivative cor responding to at least 20 times the detection limit should be injected with the recorder chart sensitivity and speed set to yield a peak approximately 755 of full scale and 1 cm wide at half height. The peak asymmetry factor is determined ft) as shown In Figure 5, and should be between 0.8 and 1.8. (jj ^ u Co & ........... -->..... ............... ... BFG15438 T05-14 14.2.3 HPLC system efficiency is calculated according to the following equation: where N = column efficiency, theoretical plates v \ * retention time of components (seconds) wl/2 = width of component peak at half height (seconds) A column efficiency of >5,000 should be obtained. Precision of response for replicate HPLC injections should be 1 OS or less, day to day, for calibration standards. Precision of retention times should be * 22, on a given day. 14.3 Process Blanks Prior to use a 10 mL aliquot of each batch of DNPH reagent should be analyzed as described in Section 11. In general,formaldehyde levels equivalent to >5 ng/L in a 60 liter sample should be achieved and other aldehyde levels should be <1 ng/L. At least one field blank should be shipped and analyzed with each group of samples. The field blank is treated identically to the samples except that no air is drawn through the reagent. The same performance criteria described in 14.3.1 should be met for process blanks. BFG15439 T05-15 14.4 Method Precision and Accuracy 14.4.1 Analysis of replicate samples Indicates a pre cision of * 15-205 relative standard deviation can be readily achieved. Each laboratory should collect parallel samples periodically (at least one for each batch of samples) to document their precision in conducting the method. 14.4.2 Precision for replicate HPLC injections should be 1^05 or .better, day to day, for calibration 14.4.3 standards. Method accuracy is difficult to assess because of the difficulty in generating accurate gaseous standards. Literature results indicate (1-3) recoveries of 755 or greater are achieved for a broad range of aldehydes. Each laboratory should periodically collect field samples wherein the Impinger solution is spiked with a known quantity of the compound of Interest, prepared as a dilute methanol solution. Formaldehyde cannot be spiked In this manner and therefore a solution of the DNPH derivative should be used for spiking purposes, 14.4. i Before Initial use of the method each laboratory should generate triplicate spiked samples at a minimum of three concentration levels, bracketing the range of interest for each compound. Triplicate nonspiked samples must also be processed. Recover ies of >70 i 205 and blank levels of <5 ng/L for formaldehyde and 1 ng/L for the other compounds (assuming a 60 liter air sample) should be achieved. CO C3 BFG15440 T05-16 References (1) Grosjean, D., Fung, K., and Atkinson, R., "Measurements of Aldehydes in the Air Environment", Proc. Air Poll. Cont. Assoc., Paper 80-50.4, 1980. (2) Grosjean, D. and Fung K., "Collection Efficiencies of Cartridges and Micro-Impingers for Sampling of Aldehydes in Air as 2,4Dinitrophenylhydrazones", Anal. Chem. 54, 1221-1224, 1982. (3) Grosjean, D., "Formaldehyde and Other Carbonyls in Los Angeles Ambient Air", Environ. Sci. Technol. 1, 254-262, 1982. (4) Riggin, R. M. , "\echnica1 Assistance Document for Sampling and Analysis of Toxic Organic Compounds in Ambient Air", EPA-600/4-83-027. U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, 1983. (5) Annual Book of ASTM Standards, Part 11.03, "Atmospheric Analysis", American Society for Testing and Material, Philadelphia, Pennsylvania, 1983. (6) Berry, D. A., Holdren, M. W., Lyon, T. F., Riggin, R. M., and Spicer, C. W., "Turbine Engine Exhaust Hydrocarbon Analysis-Interim Report on Task 1 and 2", Report on Contract No. F-08635-82-C-0131, Air Force Engineering and Services Center, Tyndall AFB, Florida, 1983. (7) Shiner, R.', Fuson, R.. and Curtin, D., "The Systematic Identification of Organic Compounds", John Wiley and Sons, Inc., 5th ed.. New York, 1964. (8) "Method 6 Determination of SO2 Emissions from Stationary Sources", Federal Register, Vol. 42., No. 160, August 1977. BFG15441 N H1 yi 3i *r> 03 ^3 T05-17 TABLE 1. ALDEHYDES AND KETONES FOR WHICH THE METHOD HAS BEEN EVALUATED Comoound Molecular Weiqht Derivative Comoound Typical Relative Retention Time(a' Formaldehyde Acetaldehyde Acrolein Propanal Acetone Crotonaldehyde IsobutyraldehydeMethyl Ethyl Ketone Benzaldehyde Pentanal o-Tolualdehyde m-Tolualdehyde p-Tolualdehyde Hexanal 210 * \ 224 236 238 238 250 252 252 286 266 300 300 300 280 30 1.0 44 1.3 56 1.6 58 1.7 58 l.g(t>) 70 2.3 72 2.4 72 2.8 106 3.2 86 3.7 120 4.8 120 5.1 120 5.3 100 5.7 (a) Using HPLC conditions shown in Figure 4. Formaldehyde *1.0 (b) Acetone background levels In the reagent prevent Its determination in most cases. SCTfriST BFG15442 21574139 BFG15443 T05-19 SAMPLING DATA SHEET (One Sampie Per Pita Sheet) PROJECT: SITE: LOCATION:___________ INSTRUMENT MODEL NO: PUMP SERIAL NO:_____ SAMPLING DATA DATE(S) SAMPLED:____ TIME PERIOD SAMPLED: OPERATOR:___________ CALIBRATED BY: \ ,T1me 1. 2. 3. 4. N. Sample Number:_______________ Start Time: _________ Stop Time: Dry Gas Meter Reading Flow Ambient Barometric Rotameter Rate,*Q Temperature Pressure, Relative Reading ml /Min c mmHg Humidity, X Comments * Total Volume Data** Vm (Final * Initial) Dry Gas Meter Reading, or 02 Q3...Qn 1 --------R------------ x I000 x (Sampling Time In Minutes) Liters Liters * Flowrate from rotameter or soap bubble calibrator (specify wtilcft). ** Use data from dry gas meter If available. FIGURE Z. EXAMPLE SAMPLING OATA SHEET tT 3i i 21574140 BFG15444 ! TOS-20 I i i r I....... I-------- 1 .... l .... 1 .... I .... L-. i-i.., 1 s s ru hQ tH 0) 00 Q oe30 r* 35 c: Formaldehyde Acetaldehyde Acrolein -- Proplonal Acetone Crotonaldehyde . Benzaldehyde Pentanal oft *n -- 3 o o fftt o * cr--e --3 50 ft 3 ft ft* ft 1 ft 3" o S' vi O ft ft o Q! 3 I or 00 X o X \ON> otO/> X' O 3 O- 3 3 Cr+ ft fXt JtNrii r3** O oO 3 03 X Xfc \ ON roO Cyclohexanone v' c r 12-S01 3. Organic Acids OSHA - 38 Dow Chemical Modifications (for Formic, Acetic and Acrylic Acids) A BFG15447 h* O] Qc ACRYLIC ACID Method no.: 28 Matrix: Air Target concentration: 2 ppm (5.9 mg/m1) see Toxic Effects Section 1.1.2. Procedure: Samples are collected' by drawing aknown volume of air through two XAD-8 sampling tubes connected in series. Samples are desorbed with 1/1 methanol/water and analyzed by high performance liquid chromatography (HPLC) using an ultraviolet (UV) detector. Recommended air volume and sampling rate: 24 L at 0.1 L/min Detection limit of the overall procedure: (Based on the recommended air volume) 0.014 ppm (0.042 mg/m1) Reliable quantitation limit: 0.014 ppm (0.042 mg/mJ) Standard error of estimate at the target concentration: (See Table 4.8.1. and Figure 4.8.1.) 7.13? Status of method: A sampling and analytical method which has been subjected to the established evaluation procedures of the Organic Methods Evaluation Branch. Date: April, 1981 Chemist: Kevin Cummins Organic Methods Evaluation Branch OSHA Analytical Laboratory Salt Lake City, Utah BFG15448 1. General Discussion 1.1. Background 1.1.1. History of procedure A numoer of analytical methods are reported in the literature for the analysis of acrylic acid. Although a polarographic method has been published, most of these methods Involve either gas, liquid, or paper chromatographic techniques (Ref. 5.1.). A direct method of analysis using reverse phase high performance liquid chromatography was developed and used in this study. This method is sensitive, selective, and easy to apply, and it also permits the simultaneous analysis of a numoer of other acrylate monomers and acrylic acid precursors. A previous attempt by Brown to use octadecasilane (ODS) based HPLC columns for the analysis of acrylic acid was unsuccessful (Ref. 5.2). It has been recognized in this laboratory for some time that polar molecules of low molecular weight can often be retained and chromatographed in the reverse phase mode using Zorbax ODS packed columns and a high percent of water in the mobile phase. This method, when coupled with an ion suppression technique, proved successful for the retention and separation of acrylic acid. A retention time of approximately six minutes is obtained with a Dupont Zorbax ODS eight-micron, silica packed column and a 96/*i, water/acetonitrile mobile phase containing 0.1% by volume of phosphoric acid. The phosphoric acid serves to suppress the ionization of acrylic acid resulting in the retention of the undissociated form of the molecule. Under these conditions acrylic acid is separated from the potential interferences: methacrylic acid, acrylamide, acrolein, acrylonitrile, and acetic acid. Propanoic acid, a saturated precursor of acrylic acid, can be resolved from acrylic acid in a 13 minute analysis at 1 mL/min flow rate using a 0.1% aqueous phosphoric acid mobile base. Acrylic acid, because of its unsaturated nature, is approximately 100 times more sensitive at 210 nm on a weight basis than propanoic acid. This method permits the detection of acrylic acid in the presence of very high levels of propanoic acid. No published data was found regarding a collection method for acrylic acid from air. In a personal communication, it was reported that silica gel tubes coated with either hydroqulnone or p-methoxyhydroquinone were being evaluated as a means of sampling acrylic acid in air (Ref. 5.1*.). Both of these compounds are commonly used in the acryllc- 28-1 BFG15449 21574145 t acrylate industry to prevent polymerisation of a variety of monomeric substances. No decomposition of acrylic acid was observed in evaluations performed at this laboratory using either hydroquinone treated or untreated silica gel tubes. It should be noted, however, that the standard used in this evaluation contained low, unspecified levels of p-methoxyhydroquinone inhibitor. Further evaluations indicated that some problems with the retention of acrylic acid on SKC silica gel tunes could arise if air sampling is being performed for nn extenoed time in humid atmospheres. No loss of acrylic acid from the front section of a silica gel tube occurred if 805 relative humidity air was sampled for one hour at a 0.1 L/min flow rate. With longer sampling times, a considerable migration from the front section of the sampling tube was observed. When *46.7 ug of acrylic acid in methanol was spiked into an atmosphere ahead of two silica gel tubes mounted in series, and humid air was drawn through the system for four hours at a 0.1 L/min flow rate, only 155 of the total analyte was retained on the front section of the first silica gel tube. (See Backup Data Section H.9., Table H.9.) Differences in retention efficiency between two different lots of SKC silica gel tubes are also apparent from this data. The recently purchased lot 119 silica gel tubes are less effective in retaining acrylic acid in a humid atmosphere than the older SKC silica gel tubes which do not have a lot number designation. (See Backup Data Section H.9., Table *4.9.) In addition to silica gel, several other solid sorbent materials were determined to be inadequate for sampling acrylic acid. Low desorption efficiencies were obtained for both charcoal and Porapak T sorbents using various ratios of methanol and water to desorb the spiked tubes. XAD-2 and XAD-H, both non-polar, styrene-divinyl benzene copolymers, gave 1005 desorption efficiencies using methanol. However, neither of these two sorbents were totally effective in retaining acrylic acid when humid air was sampled. Six XAD-2 tubes retained an average of only 605 of 120 ug acrylic acid spikes wnen 805 relative humidity air was drawn through each tube for three hours at a 0.1 L/min flow rate. Although more effective in retaining acrylic acid than XAD-2, the higher surface area XAD-& sorbent still lost an average of 205 of a 327 ug acrylic acid spike when 805 relative humidity air was drawn through duplicate sample tubes at a 0.1 L/min flow rate for 7.5 hours. Further studies on the collection of acrylic acid from air indicated that the solid sorbent, XAD-8, an acrylic ester polymer, was quite effective in collecting and retaining acrylic acid. Ol a $ 28-2 BFG15450 Amounts equivalent to twice the target concentration for a four-hour air sample 1327 ug) could be spiked into an atmosphere anead of the sampling tube and effectively collected and recovered after 80J relative humidity air is drawn through the tube for four hours at 0.1 L/min. No breakthrough onto a second tube mounted in series was observed for acrylic acid collected from a spiked atmosphere, even though 80S relative humidity air was drawn through the system for 8 hours. Similar results were observed when relatively dry laboratory air was sampled. (See Backup Data Section U.5.) Although no problems were encountered with the use of XAD-fl in sampling for acrylic acid, it should be noted that there exists a similar polymeric acrylic ester, XAD-7, which because of its higher surface area may be a more effective sampling media for low molecular weight, polar substances. (Ref. 5.5) However, based on the evaluation procedures performed to date, an XAD-8 sorbent packed tube is currently recommended as the sampling media for acrylic acid in air. 1.1.2. Toxic Effects (This section is for information only and should not be taken as the basis of GSHA policy). Acrylic acid is an acute local Irritant. Exposure to its vapors can produce an irritating effect to the skin, eyes, nasal and bronchial passages. (Ref. 5.3) An exposure of 300 ppm for six hours per day for 20 .days resulted in nasal irritation, lethargy, and weight loss in three male and three female rats. A one time, five-hour exposure at saturated conditions (6000 ppm) produced nose and eye irritation, respiratory impairment, and death in one of four exposed rats. (Ref. 5.6.) A large variability in the ID,, value is reported for both rabbits and mice. LD,, values for a single skin application ranging rrom 295 mg/kg bw (body weight) to 950 mg/kg bw are reported in rabbits. Oral LD,a values in rats vary from 193 mg/kg bw to 3200 mg/kg bw. (Ref. 5-1.) In a fetal rat toxicity study conducted by Singh, et al, a dose related increase in the incidences of skeletal abnormalities. reduced birth weights, and resorptions was observed with exposure of pregnant rats to acrylic acid. (Ref. 5.7.) The authors note however, that the effects observed by acrylic acid and several methacrylate esters were not as pronounced as was observed for phthalate ester treated rats in previous studies. 21574147 28-3 BFG15451 The International Agency for Research in Cancer (IARC) reports that there is no data available regarding the carcinogenic potential of acrylic acid, and recommends study in this area. (Ref. 5.1.) The recommended target concentration of 2 ppm is based on the results of a recent industry sponsored subchronic- inhalation study of mice and rats. A slight focal degeneration of the olfactory mucosa was observed in a portion of the mice exposed to 5 ppm acrylic acid for 90 days. The 2 ppm level is a suggested TWA exposure limR of the Health and Safety Division of Rohm and Haas. (Ref. 5.8.) 1.1.3. Exposure Exposure to acrylic acid vapors is primarily confined to production processes since most acrylic acid is used as a precursor in the production of a variety of different acrylates. The alkyl esters of acrylic acid are used to produce a number of products Including acrylic fibers, emulsion and solution polymers, and surface coatings. Some of the free acid is used to produce polyacrylic acid, which has industrial uses as a thickener, flocculant, and binder. In 1976 three U.S. companies reported a production of 116.5 million kg of acrylic acid. (Ref. 5.1., 5.3.) 1.1.*. Physical Properties (Ref. 5.9. unless otherwise indicated) M.W.: 72.06 Solubility: Miscible in alcohol and ether. Soluble in acetone and benzene. B.P.: 1*1 *C at 760 mm Flash Point: 155#F (Ref. 5.10.) Cleveland open cup. Specific Gravity: 1.05 (20/*#C) Color: Clear, colorless (Ref. 5.10.) Odor: Pungent, irritating, odor resembling acetic acid. (Ref. 5.10.) Formula: H,C-CHCOOH Synonyms: Acroleic acid, propcnoic acid, ethylene carboxylic acid, propene acid, vinyl formic acid (Ref. 5.11.) 21574148 28-* BFG15452 1.2. Limit defining parameters 1.2.1. Detection limit of the analytical procedure The detection limit of the analytical procedure is 5 ng per injection. This is the amount of analyte unic.n will give a peak whose height is five times the amplitude of the baseline noise. (See Backup Data Section 4.1., Figure 4.2.). 1.2.2. Detection limit of the overall procedure The detection limit of the overall procedure is 1 ug per sample (0.015 ppm/0.042 mg/m5). This is the amount of analyte spiked on the sampling device which allows recovery of an amount of analyte equivalent to the detection limit of the analytical procedure. (See backup data section 4.2.) 1.2.3. Reliable quantitation limit The reliable quantitation limit is 1 ug per sample (0.014 ppm/0.042 mg/m5). This is the smallest amount of analyte which can be quantitated within the. requirements of 755 recovery and 955 confidence limits oif 255. (See Backup Data Section 4.3.) It must be recognized that the reliable quantitation limit and detection limits reported in the method are based upon optimization of the instrument for the smallest possible amount of analyte. When the target concentration of an analyte is exceptionally higher than these limits, they may not be attainable at the routine operating parameters. In this case, the limits reported on analysis reports will be based on the operating parameters used during the analysis of the samples. 1.2.4. Sensitivity The sensitivity of the analytical procedure over a concentration range representing 0.5 to 2 times the target concentration based on the recommended air volume is 12,415 area units per ug/mL. The sensitivity is determined by the slope or the calibration curve. (See Backup Data Section 4.4., Figure 4.4.) The sensitivity will vary somewhat with the particular Instrument used in the analysis. 28-5 BFG15453 1.2.5. Recovery The average recovery from spiked samples over the range of 0.5 to 2 times the target concentration is 1025. (See Backup Data Section Table 4.7.) The recovery of analyte from the collection medium must be 755 or greater. 1.2.6. Precision (Analytical method only) The pooled coefficient of variation obtained from eight replicate determinations of analytical standards at 0.5X, IX and 2X the target concentration is 0.0085. (See Backup Data Section 4.6.) 1.2.7. Precision (Overall Procedure) The overall procedure must provide results at the target concentration that are +255 or better at the 955 confidence level. The average precision at the 955 confidence level for the ambient storage tests is + 145. (See Backup Data Section Figure 4.8.1. and Table 4.8.1.) This includes an additional +55 for sampling error. 1.3. Advantages 1.3.1. The sensitivity of the analytical method permits sampling times as short as 15 minutes. 1.3*2. HPLC analysis of acrylic acid is rapid, direct, and sensitive. 1.3*3* Reanalysis of samples is possible. 1.4. Disadvantages The method has not been field tested at this time. 2. Sampling Procedure 2.1. Apparatus 2.1.1 2.1.2 A personal sampling pump which can be calibrated to within 55 of tne recommended 0.1 L/min flow rate while the sampling tubes are in line. Class tubes of 4- to 5~cm length with a 4-tnm ID and a 6-mm OD are packed with approximately 100 mg of XAD-8 solid sorbent of 16-50 mesh size. Small silanized glass wool plugs on each end of the tube nre used to retain the sorbent. These packed XAD-8 tubes are currently available from the laboratory upon request. f\; oc* 28-6 BFG15454 April 6,1990 Dr. Rafael Moure University of Lowell METHOD FOR THE ANALYSIS OF ORGANIC ACIDS IN AIR Dear Dr. Moure: This is a brief description of the organic adds analysis method that we discussed on the phone earlier today. Formic, acetic, and acrylic adds can be collected simultaneously on silica gel tubes (700 mg front/300 mg back), with a flow of about 100 mL/mln. The acids are then desorbed using de-ionized water (typically 10 mL), with a 1-hou. 'action (we use a flatbed shaker). We have typically seen recov n excess of 90%, but we always run some spiked tubes with our sam: o confirm the recoveries. The extraction solvent is then analyzed using high-performance liquid chromatography (HPLC). The column we have found to work the best is an Aminex HPX-87H ion exclusion column (7.8 x 300 mm), which is manufactured by Bio-Rad Laboratories (32 nd Street, Richmond, CA 94804, catalog # 125-0140). The eluent was 0.01 N H2SO4 at a flow' of 1 mL/mln. U V. detection at 208 nm was used, which was fed into our laboratory data system. Retention times for formic, acetic and acrylic adds were about 8.4, 9.3, and 11.8 minutes, respectively. The limit of detection for formic and acetic acid was about 1 ng/mL in solution, while the LOD for acrylic acid was about 0.1 4g/mL. With a desorption volume of 10 mL and an air sample volume of about 20 L, the corresponding LOD's In air are around 0.2 ppm and 0.02 ppm, respectively. Some -epresentative chromatograms are shown on the next page. If you have any further questions, please do not hesitate to give me a call. inrpr^lv. 1 ,, HicES Analytical Chemistry The Dow Chemical Company 1803 Building Midland, MI 48674 (517) 636-0629 BFG15455 CR 4. Aerosol Sampling * Total Dust NIOSH -0600 BFG15456 ZSTW.STZ FORMULA: The respirable fraction of the ___ dust mass, as specified by the American Conference of Governmental Industrial Hygienists [1] NUISANCE DUST, RESPIRABLE METHOD: 0600 ISSUEO: 2/15/84 OSHA: 5 mg/m* NIOSH: no standard ACGIH: S mg/m1 PROPERTIES: Penetrates the non-ciliated portions of the lung; quartz less than SYNONYMS: boron oxide (CAS #1303-86-2) and nuisance dusts [2], including alumina (CAS #1344-28-1), calciun carbonate (CAS #1317-65-3), cellulose (paper fiber; CAS #9004-34-6), glycerin mist (CAS #S6-81-5), limestone (CAS #1317-65-3), etc. SAMPLING_________________________________________ MEASUREMENT SAMPLER: CYCLONE * FILTER (10-flin Dorr-Oliver cyclone tared 5-gm PVC menfcrane) TECHNIQUE: GRAVIMETRIC (FILTER WEIGHING) ANALYTE: mass of respirable dust fraction FLOW RATE: 1.7 L/min VOl-MIN: 75 L 9 5 mg/m* -MAX: 1000 L 9 5 mg/m* SHIPMENT: routine SAMPLE STABILITY: indefinitely BALANCE: 0.01 mg sensitivity or better; use same balance before and after sample collection CALIBRATION: National Bureau of Standards Class N weights RANGE: 0.3 to 2 mg per sample BLANKS: 2 to 10 field blanks per set ESTIMATED LOO: 0.2 mg per sample ACCURACY PRECISION: 68 pg with 0.01-mg sensitivity balance [5] RANGE STUDIED: 0.5 to 10 mg/m* (lab and field) BIAS: depends on dust size distributions [3] OVERALL PRECISION (sp): 0.043 to 0.145 (lab); 0.144 to 0.227 (field) (4] APPLICABILITY: The method measures the mass concentration of any non-volatile respirable Aist. Besides inert dusts [1], the method is recamended for respirable coal dust, which has an OSHA PEL 2.4 mg/m*. The method may be biased where the respirable fraction is defined by the British Medical Research Council's criteria or the MRE horizontal elutriator [43. INTERFERENCES: Larger than respirable particles (over 10 pm) have been found in seme cases by microscopic analysis of cyclone filters. Over-sized particles in the sanple are known to be caused by inverting the cyclone assembly. Heavy dust loadings, charged particles, fibers and water-saturated dusts also interfere with the cyclone's size-selective properties. OTHER HETHOOS: This method is based on and replaces Sampling Data Sheet #29.02 [6]. _ 1574153 2/15/04 0600-1 BFG15457 NUISANCE DUST. RESPIRABLE HET1P0: 0600 EQUIPMENT: ,, 1. Sampler: a. Filter: 37-mn diameter, 5.0-ym pore size, polyvinyl chloride filter or equivalent hydrophobic membrane filter supported with backup pad in a two-piece, 37-mn cassette filter holder held together by tape or cellulose shrink band. b. Cyclone: 10-mu Dorr-01iver nylon cyclone. c. Sampling head holder: this holder must keep the cassette, cyclone and coupler together rigidly so that air enters only at the cyclone inlet. 2. Personal sampling pump, 1.7 L/min 51, with flexible connecting tubing. NOTE: Pulsation in tlie pump flow must be within 201 of the mean flow. 3. Balance, analytical, with sensitivity of at least 0.01 mg. A more sensitive balance will be necessary for substances with PEL'S below 1 mg/m*. 4. Static neutralizer, e.g., Po-210; replace nine months after the production date. 5. Environmental chamber for balance, e.g., 20 *C 0.3 *C and 501 + 51 RH. 6. Vacuum desiccator. SPECIAL PRECAUTIONS: None.* 1 2 3 4 5 6 7 8 9 PREPARATION OF SAMPLERS BEFORE SAMPLING: 1. Dry filters and backup pads under vacuum in the vacuum desiccator for at least 15 min. 2. Release the vacuum, remove the desiccator cover, and equilibrate the filters in the environmental chamber for at least 1 hr. 3. Number the backup pads with a ballpoint pen and place them, mnbered side down, in filter cassette bottom sections. 4. Weigh the filters in the environmental chamber. Record the filter tare weight, Wj (mg). a. Zero the balance before each weighing; .. b. Handle the filter with forceps (nylon forceps if further analyses will be done); and c. Pass the filter over an antistatic radiation source. Repeat this step if filter does not release easily from the forceps or if filter attracts balance pan. Static electricity can cause erroneous weight readings. 5. Place the weighed filters on top of the backup pads in the filter cassette bottom sections and allow to stand an additional 8 to 16 hrs in the environmental chanber. 6. Reweigh the filters. If this tare weight differs by more than 0.01 mg from the first tare weight obtained in step 4 above, discard the filter. ' NOTE: Insert a rod through the outlet hole of the filter cassette bottom section to raise the backup pad and filter so that the filter can be grasped with forceps. 7. Assentle the filters in the filter cassettes and close firmly so that leakage around the filter will not occur. Place a plug in each opening of the filter cassette. Place a cellulose shrink band around the filter cassette, allow to dry, and mark with the same nirber as the backup pad. 8. Remove the cyclone's grit cap and vortex*finder before use and inspect the cyclone interior. If the inside is visibly scored, discard this cyclone since the dust separation characteristics of the cyclone might be altered. Clean the.interior of the cyclone to prevent reentrainment of large particles. 9. Assenble the sampler head. Check alignment of filter holder and cyclone in the sampling head to prevent leakage. US K 2/15/84 0600-2 BFG15458 HEIHOO: 0600 NUISANCE DUST. RESPIRABLE SAMPLING: 10. Calibrate each personal sanpling pump to 1.7 L/min with a representative sanpler in line. 11. Sanple at 1.7 l/min for 45 min to 8 hrs (76 to 816 l). Do not exceed 5 mg dust loading on the filter. '! NOTE: Do not allow the sanpler assembly to be inverted at any time. Turning the cyclone to anything more than a horizontal orientation may deposit over-sized material from the cyclone body onto the filter. SAMPLE PREPARATION: 12. Wipe dust from the external surface of the filter cassette with a moist paper towel to minimize contamination. Discard the paper towel. .13. Remove the top and bottom plugs from the filter cassette. Place the filter cassettes in a vacuum desiccator under vacuun for at least 15 min, followed by equilibration for at least 1 hr in the environmental chanber. 14. Remove the filter cassette band, pry open the filter cassette, and remove the filter by inserting a rod in the outlet hole of the filter cassette. Handle the filters very gently by the edge to avoid loss of dust. NOTE: If the filter sticks to the underside of the cassette top, very gently lift away by using the dull side of a scalpel blade. This must be done carefully or the filter will tear. CALIBRATION AND QUALITY CONTROL: 15. 2ero the microbalance before all weighings. Use the same microbalance for weighing filters before and after sanple collection. Calibrate the balance with National Bureau of Standards Class H weights. 16. Take two to four replicate samples for every batch of field sanples for quality assurance on the sanpling procedures. The set of replicate samples should be exposed to the same (hist environment, either in a laboratory dust chanber [7] or in the field [8]. .The quality control sanples must be taken with the same equipment, procedures and personnel used in the routine field samples. Calculate precision fron these replicates and record sr on control charts. Take corrective action when the precision is out of control [7], MEASUREMENT: 17. Weigh each filter, including field blanks. Record this post-sanpling weight, 2 (mg), beside its corresponding tare weight. Record anything remarkable about a filter (e.g., visible particles, overloaded, leakage, wet, tom, etc.). CALCULATIONS: 18. Calculate the concentration of respirable nuisance (hist, C (mg/m*), in the air volune sanpled, V (L): C . >/. where: Wj * tare weight of filter before sanpling (mg) W2 s post-sarpling weight of sanple-containing filter (mg) B trean change in field blank filter weights between tare and post-sanpling (mg) (or-). 21574155 2/15/84 0600-3 BFG15459 NUISANCE DUST. RESPIRABLE WETHOP: Q600 EVALUATION OF NETHOO: 1. Bias. In respirable dust measurements, the bias in a sample is calculated relative to the appropriate respirable dust criterion. The theory for calculating bias is developed by Bartley and Breuer [3]. For this method, the bias, therefore, depends on the ACGJH criterion for respirable dust, the cyclone's penetration curve at 1.7 l/min flow rate, and the size distribution of the ambient dust. Based on the cyclone's penetration curves for non-pulsating flow measured with a monodisperse aerosol by Caplan, Doemeny and Sorenson [9], the bias in this method is shown in Figure 1. For dust size distributions in the shaded region, the bias in this method lies within the t 0.10 criterion established by NIOSH for method validation. Bias larger than 0.10 would, therefore, be expected for many workplace aerosols, especially those with small mass median diameters. However, bias within 0.20 tnuld be expected for dusts with geometric standard deviations greater than 2.0, which is the case in most workplaces. Bias can also be caused in a cyclone by the pulsation of the personal sanpling purrp. Bartley, et al. [10] showed that cyclone samples with pulsating flow can have negative bias as large as -0.22 relative to samples with steady flow. The magnitude of the bias depends on the amplitude of the pulsation at the cyclone aperture and the dust size distribution. For pumps with instantaneous flow rates within 201 of the mean, the pulsation bias is less than -0.02 for most dust size distributions encountered in the workplace. Electric charges on the dust and the cyclone will also cause bias. Briant and Moss [11] have found electrostatic biases as large as -501, and show that cyclones made with graphite-filled nylon eliminate the problem. 2. Precision. In a recent review [4], the overall cyclone precision is shown to be most sensitive to two factors: the analytical precision and the sanpling procedures,, particularly the quality control system used in the maintenance and calibration of samplers. Theoretically, the variance for the overall precision is the sum of the variances from the sanpling and analysis. The analytical variance depends on the dust loading on the filter. For the dust loading in an 8-hr sanple above 1.5 mg/m*, Bownan, et al. [4] find that the empirically determined sanpling error dominates this analytical error. Because of the effects of the environment, precision estimates for dust samplers are much more variable than those reported for gas and vapor sanpling. In laboratory tests with 0.01 mg sensitivity balances, the overall precision of a single respirable dust sanple has relative standard deviations (sr) from 0.043 to 0.145 over concentrations ranging from 0.5 to 5 mg/m*. In the laboratory studies where the <fcist concentrations in the test chamber are more carefully controlled, the estimated sr is less than 0.091, which is the target precision value for a bias equal to + 0.10 in the NIOSH validation criteria. In the field tests with 0.01 mg sensitivity balances, precision estimates range from 0.144 to 0.227 over concentrations ranging from 1 to 10 mg/m*. Hhather the larger sr values in field tests are due to sampler performance or to more inhomogeneous dust concentrations in the field tests cannot be determined from existing data. 2/15/84 0600-4 ot 07 a BfG\5460 HETHOO: 0600 NUISANCE DUST. RESPIRABLE REFERENCES: [1] TLVs - Threshold Limit Values for Chemical Substances and Physical Agents in the Work Environment with Intended Changes for 1983-84, 38, ACGIH, Cincinnati, OH (1983). [2] Ibid, Appendix D, 52. [3] Bartley. 0. L. and G. H. Breuer. Analysis and Optimization of the Performance of the 10-nm Cyclone, Am. Ind. Hyg. Assoc. J., 43 . 520-528 (1982). [4] Bowman, J. 0., 0. L. Bartley, G. H. Breuer and S. A. Shulman. The Accuracy of Sanpling Respirable Coal Nine Dust, Draft NIOSH report (1963). [5] Parobeck, P., T. F. Tort), H. Ku and J. Cameron. Measurement Assurance Program for the Weighings of Respirable Coal Nine Dust Samples, 0. Qua). Tech.. T3, 157 (1981). [6] NIOSH Manual of Sampling Data Sheets, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77-159 (1977). [7] Bowman, J. 0., D. 1. Bartley, G. N. Breuer, l. J. Doemeny and D. 0. Nurdock. Accuracy Criteria Recomnended for the Certification of Gravimetric Coal Nine Dust Personal Samplers, NIOSH report (in press, 1983). [8] Breslin, 0. A., S. 3. Page and R. A. Jankowski. Precision of Personal Sampling of Respirable Dust in Coal Hines, U.S. Bureau of Nines Report of Investigations #8740(1983). [9] Caplan, K. J.. L. J. Doemeny and S. Sorenson. Evaluation of Coal Nine (hist Personal Sanpler Performance, Final Report, NIOSH Contract No. PH CPE-r-70-0036 (1973). [10] Bartley, 0. 1., G. H. Breuer, P. A. Baron and J. 0. Bownan. Puip Fluctuations and Their Effect on Cyclone Performance, submitted to the Am. Ind. Hyg. Assoc. J. (1983). [11] Briant, J. K. and 0. R. Moss. The Influence of Electrostatic Charge on the Performance of 10-mm Nylon Cyclones, American Industrial Hygiene Conference (1983). METHOD WRITTEN BY: Joseph Bownan, Ph.0., CIH, NIOSH/OPSE. j <> . 2/15/84 0500-5 BFG15461 H* U s F4 u wilSANCE DUST. RESPIRABLE HETHOO: 0600 MASS MEDIAN DIAMETER (pm ) Figure 1. Bias in respirable dust determination. 2/15/84 0600-6 ui tr co BFG15462 4. Aerosol Sampling * Benzene Soluble Particulate NIOSH - 5023 BFG15463 1574159 FORMULA: various organic-soluble compounds [1.2.3] M.W.: various COAL TAR PITCH VOLATILES METHOO: 5023 ISSUED: 5/15/85 OSHA: 0.2 mg/m* (benzene-solubles) NIOSH: 0.1 mg/m*/10 hr (cyclohexane-solubles) [2,3] ACGIH: 0.2 mg/m* (benzene solubles) [4J PROPERTIES: liquid; d -1.06 g/mL 9 38 *C; 60 to 85% distills 8 <355 *C [5]; creosote distills 9 270 to 395 *C [2] SYNONYMS: benzene-solubles, cyclohexane-solubles, coal tar pitch volatiles (CAS *8007-45-2), creosote from coal tar. SAMPLING________________________ __________________ MEASUREMENT SAMPLER: FILTER (2-ym, 37-rnn PTFE membrane) FLOW RATE: 1 to 4 L/min VOL-MIN: 500 L 9 0.2 mg/m* -MAX: 2400 L SHIPMENT: routine SAMPLE STABILITY: unknown FIELD BLANKS: 101 (>2) of samplers TECHNIQUE: GRAVIMETRIC ANALYTE: organic-solubles (includes anthracene, benzanthracene, benzo(a)pyrene, carbazole, chrysene, phenanthrene, pyrene and others [1,2,3,4]) EXTRACTION: benzene, cyclohexane or other appropriate solvent; ultrasonic 20 min CALIBRATION: National Bureau of Standards Class M weights ACCURACY RANGE STUOIED: not studied BIAS: unknown RANGE: 0.1 to 2 mg per sample ESTIMATED LOO: 0.05 mg per sanple [6] PRECISION (sr): 0.02 at 1.35 mg [6]; 0.23 for blanks [6] OVERALL PRECISION (sp): not determined APPLICABILITY: The working range is 0.1 to 2 mg/m* for a 1000-L air sample. The method is useful for air monitoring of coke oven emissions, petroleun combustion products such as diesel emissions, and petroleun asphalt funes. The method may be applied to bulk samples. The method is non-specific and measures all substances in the sample which are soluble in the solvent selected and which can be desorbed from particulate matter present on the filter. INTERFERENCES: Changes in temperature or hunidity during pre- and post-collection weighing affect accuracy. Losses may occur due to volati1ization of collected aerosol (hiring or after sampling. OTHER METHOOS: This method modifies and carbines P&CAM 217 [7] and the criteria document method [2]. 5/15/85 5023-1 BFG15464 COAL TAR PITCH VOLATILES REAGENTS: 1. Solvent: Benzene,* cyclohexane or other solvent, reagent grade. 2. Oichromic acid cleaning solution. 3. Acetone, reagent grade. 4. Hexane. See SPECIAL PRECAUTIONS. METHOD: 5023 EQUIPMENT: 1. Sampler: PTFE laminated mortorane filter, 2-pm pore size, 37-nrn diameter (Zeflour, Hembrana Inc., Pleasanton, CA or equivalent) backed by a gasket (37 tm 00, 32 mu ID) cut from a cellulose support pad in plastic filter holder. 2. Personal sanpling punp, 1 to 4 L/min, with flexible connecting tubing. 3. Ultrasonic bath. 4. Microbalance, readable to 1 pg, with' MBS Class M weights. 5. Environmental chamber for balance, e.g., 20 *C 0.3 *C and SOI 51 relative humidity. 6. Weighing cups, PTFE, 2-mL, approximate tare weight 60 mg, in metal rack. 7. vaeutm oven. NOTE: keep the interior of the vacuum oven dust-free for maxinun sensitivity, reproducibility, and accuracy. 8. Forceps. 9. Test tubes, PTFE-lined, screw cap, 13 am x 100 im.* 10. Filter, 0.5-im (Millex-SR, Millipore Corp., Bedford, HA or equivalent). 11. Pipets, 1- and 5-mL.* *Rinse with distilled water, acetone, and hexane; dry. i i SPECIAL PRECAUTIONS: Benzene and coal tar pitch volatiles are suspect carcinogens [1,2,3,4). SAMPLING: , *1 2 3 4 5 6 1. Calibrate each sanpling putp with a representative sanpler in line. 2. Sample at an accurately known flow rate between 1 and 4 l/min for a total sanple volune of 500 to 2400 L. Do not exceed a filter loading of ca. 2 mg total particulate. 3. Replace caps in cassette and ship to laboratory. SAMPLE PREPARATION: 4. Transfer filter carefully using forceps to test tube. Add 5.0 ml solvent via pipet. Cap the tube. NOTE 1: Cyclohexane is recommended as solvent because of the carcinogenic potential of benzene [2]. NOTE 2: This extraction is also applicable to bulk samples (ground and sieved to ca. 250 pm). Extract 250 mg bulk sanple with 5.0 mL solvent. 5. Place tube upright in beaker containing water to the same level as the liquid in the tube. Place beaker and tube in ultrasonic bath. Sonicate for 20 min. 6. Filter solution through a 0.5-pm filter into a clean, preweighed weighing cup. Discard the filter. NOTE: An aliquot of the solution may be taken at this step if other analyses (e.g., polynuclear aromatic hydrocarbons) are to be performed on the sample. Apply the appropriate aliquot factor in calculations. 5/15/85 5023-2 BFG15465 METHOO: 5023 COAL TAR PITCH VOLATILES CALIBRATION ANO QUALITY CONTROL: 7. Zero the microbalance on the 1.0 mg range and calibrate per balance manufacturer's directions. NOTE: Perform weighings at constant temperature and relative hunidity. 8. Process three blank filters through the extraction and measurement procedures. MEASUREMENT: 9. Transfer via pipet a 1.0-mL aliquot of sanple extract to a preweighsd weighing cup. 10. Place weighing cup in vacuun oven preheated to 40 *C. Apply vacuun until pressure in the oven is 7 to 27 kPa (50 to 200 ntn Hg). Allow solvent to evaporate for 2 hrs. Release vacuun by slowly opening release valve which has an in-line filter to remove room dust. 11. Equilibrate the weighing cup to the temperature and relative tumidity of the balance room for at least 30 min. Weigh the weighing cup to the nearest microgram. CALCULATIONS: 12. Determine the mass of organic-soluble residue found in the sanple, W (pg), and in the average media blank, B (pg). 13. Calculate concentration, C, of organic-solubles in the air volume sampled, V (L): C . (W 5. ng/n,*. EVALUATION OF METHOO: Several benzene extracts of samples of a1 uninun reduction plant emissions were combined to give a solution containing 1.35 mg of benzene-soluble material per sample; nine aliquots of this solution gave residue weights with a relative standard deviation of 0.02. Benzene extracts of six blank filters gave residue weights with a relative standard deviation of 0.23 [7]. REFERENCES: [1] NIOSH/OSHA Occupational Health Guidelines for Chemical Hazards, Coal Tar Pitch Volatiles, U.S. Department of Health and Hunan Services, Publ. (NIOSH) 81-123 (1981), available as GPO Stock #017-033-00337-8 from Superintendent of Docunents, Washington, 0C 20402. [2] Criteria for a Reconmended Standard ... Occupational Exposure to Coal Tar Products, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 78-107 (1978). [3] Criteria for a Reconmended Standard ... Occupational Exposure to Coke Oven Emissions, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 73-11016 (1973). [4] Docunentation of the Threshold Limit Values, 4th ed., American Conference of Governmental Industrial Hygienists, Cincinnati, OH (1981). [5] The Merck Index, 9th ed.. #2563, Merck 4 Co., Rahway, NO (1976). [6] UBTL Report, NIOSH Sequences #4229-T,U.V (unpublished. April 27, 1984). [7] NIOSH Manual of Analytical Methods, 2nd ed., Vol. 1, P4CAH 217, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77-157-A (1977). METHOO REVISED BY: B. R. Bel inky. NIOSM/OPSE. 5/15/85 5023-3 :* S-. cn O') BFG15466 4. Aerosol Sampling * Lead NIOSH - 7082 BPGl54fij 21574-163 ! FORMULA: Pb H.U.: 207.19 (Pb); 223.19 (PbO) METHOD: ISSUED: LEAD 7082 2/15/84 OSHA: 0.05 mg/m* NI0SH: 0.05 mg/m* [1] ACGIH: 0.15 mg/m*; STEL 0.45 mg/a* PROPERTIES: soft metal; d 11.3 g/on*; HP 327.5 *C; valences >2, <4 in salts SYNONYMS: vary depending upon the chemical form (elemental lead and lead compounds except alkyl lead); CAS *1317-36-8 (PbO); CAS *7439-92-1 (Pb). SAMPLING MEASUREMENT SAMPLER: FILTER (0.8-pm cellulose ester membrane) FLOW RATE: 1 to 4 L/min VOL-MIN: 200 L 8 0.05 mg/m* -MAX: 1200 L TECHNIQUE: ATOMIC ABSORPTION. FLAME ANALYTE: lead ASHING: cone. HNO3, 6 mL; 140 *C FINAL SOLUTION: 101 HNO3, 10 mL SHIPMENT: routine FLAME: air-acetylene, oxidizing SAMPLE STABILITY: stable WAVELENGTH: 283.3 nm BLANKS: 2 to 10 field blanks per set BACKGROUND CORRECTION: Dj or H2 lamp ACCURACY RANGE STU0IED: 0.13 to 0.4 mg/m* [2]; 0.15 to 1.7 mg/m* (fune) [3] CALIBRATION: Pb++ in 101 HNO3 RANGE: 10 to 200 pg per sample [3,8] ESTIMATED LOO: 2.6 pg per sample [9] BIAS: not significant [2] PRECISION (sr): 0.03 [2] OVERALL PRECISION (sr): 0.072 [2]; 0.068 (fune) [3] APPLICABILITY: The working range is 0.025 to O.S ag/a* for a 400-1 air sanple. The method is applicable to elemental lead, including Pb fuae, and all other aerosols containing lead. This is an elemental analysis, not compound specific. Aliquots of the samples can be analyzed separately for additional elements. INTERFERENCES: Use O2 or 2 continuun background correction to control flame or molecular absorption. High concentrations of calcius, sulfate, carbonate, phosphate, iodide, fluoride, or acetate can be corrected. OTHER METHODS: This method centoines and replaces P&CAH 173 [8] and S341 [7,9] for lead. Method 7300 (ICP-AES) is an alternate analytical method.Method 7505 is specific for lead sulfide. The following have not been revised: the dithizone method, which appears in P6CAH 102 [4] and the lead criteria docunent [1]; P4CAH 191 (ASV) [5]; and PBCAH 214 (graphite fumace-AAS) (61._______________ __ 2/15/84 7082-1 fr9 IV IS T ? . BFG15468 LEAP METHOD: 7082 REAGENTS: 1. Nitric acid, cone. 2. Nitric acid, 101 (w/v). Add 100 ml cone. HNO3 to 500 ml water; dilute to 1 l. 3. Hydrogen peroxide, 301 (w/w), reagent grade. 4. Calibration stock solution, 1000 yg Pb/ml. Camercial standard or dissolve 1.00 g Pb metal in mininun volune of (Ul) HC1 and dilute to 1 l with 1% (v/v) HC1. Store in a polyethylene bottle. Stable > one year. 5. Air, compressed, filtered. 6. Acetylene. 7. Distilled or deionized water. EQUIPMENT: 1. Sampler: Cellulose ester filter, 0.8-tm pore size, 37-ntn diameter; in cassette filter holder. 2. Personal sampling puip, 1 to 4 i/min, with flexible connecting tubing. 3. Atomic Absorption Spectrophotometer with an air-acetylene burner head. 4. Lead hollow cathode lamp or electrode dischargeless lamp. 5. Regulators, two-stage, for air and acetylene. 6. Beakers, Phillips, 12S mL, or Griffin, SO ml with watchglass covers.* 7. Volumetric flasks, 10- and 100-el.* 8. Assorted volumetric pipets as needed.* 9. Hotplate, surface temperature 140* C. 10. Bottles, polyethylene, 100-mL. *Clean all glassware with cone, nitric acid and rinse thoroughly with distilled or deionized water before use. SPECIAL PRECAUTIONS: Perform all acid digestions in a fune hood. SAMPLING: 1. Calibrate each personal sampling puip with a representative sampler in line. 2. Sample at an accurately known flow rate between 1 and 4 L/min for up to 8 hrs for TVM measurements. Do not exceed a filter loading of ca. 2 mg total dust. SAMPLE PREPARATION: NOTE: The following sample preparation gave quantitative recovery (see EVALUATION OF METHOO) [9]. Steps 4 through 9 of Method 7300 or other quantitative ashing techniques may be substituted, especially if several metals are to be determined on a single filter. 3. Open the cassette filter holders and transfer the samples and blanks to clean beakers. 4. Add 3 mL cone. HNO3, and 1 mL 301 HjOj and cover with a watchglass. Start reagent blanks at this step. NOTE: If Pb02 is not present in the sample, the 301 need not be added [3,9]. 5. Heat on hotplate (140 *C) until most of the acid has evaporated. 6. Repeat two more times using 2 mL cone. HNO3 and 1 mL 301 H^ each time. 7. Heat on 140 *C hotplate until a white ash appears. 8. When swple is dry, rinse the watchglass and walls of the beaker with 3 to 5 mL 101 HNO3. Allow the solution to evaporate to dryness. 9. Cool each beaker and dissolve the residues in 1 mL cone. WIO3. 10. Transfer the solution quantitatively to a 10-mL volunetrie flask and dilute to volume with distilled water. NOTE: If the concentration (M) of any of the following is expected to exceed the lead concentration (H) by 10-fold or more, add 1 ml 1 M Ma^TA to each flask before dilution to volune: OOg, POj*, I", F~, CH3COO*. If Ca** or SOJ are present in 10-fold excess, make all standards and samples 11 (w/w) in la~ [8]. W- -4 4> 2/15/84 7082-2 Otn 6^Gl5469 METHOO: 7082 LEAD CALIBRATION AND QUALITY CONTROL: IT. Prepare a series of working standards covering the range 1 to 20 yg Pb/a1 (1 to 200 yg Pb per sanple) by adding aliquots of calibration stock solution to 100-mL volunetric flasks. Dilute to volume with 101 HNO3. Store the working standards in polyethylene bottles and prepare fresh weekly. 12. Analyze the working standards together with the blanks and sanples (steps 17 and 18). 13. Prepare a calibration graph of absorbance vs. solution concentration (yg/mL). 14. Aspirate a standard for every 10 samples to check for instrument drift. 15. Check recoveries with at least one spiked media blank per 10 samples. 16. Use method of additions occasionally to check for interferences. MEASUREMENT: 17. Set spectrophotometer as specified by the manufacturer and to conditions on page 7082-1. NOTE: An alternate wavelength is 217.0 na [10]. Analyses at 217.0 nm have slightly greater sensitivity, but poorer signal-to-noise ratio compared to 283.3 nm. Also, non-atonic absorption is significantly greater at 217.0 nm, making the use of O2 or 2 continuum background correction mandatory at that wavelength. 18. Aspirate standards, samples, and blanks. Record absorbance readings. NOTE: If the absorbance values for the samples are above the linear range of the standards, dilute with 101 HNO3, reanalyze, and apply the appropriate dilution factor in the calculations. CALCULATIONS: 19. Using the measured absorbances, calculate the corresponding concentrations (yg/mL) of lead in the sample, C^, and average media blank, Cj,, from the calibration graph. 20. Using the solution volunes (mL) of the sample, Vs, and media blanks, V&, calculate the concentration, C (mg/m*), of lead in the air voluae sanpled, V (L): C - ^>Vb. ng/m*. EVALUATION Of METHOO: Method S241 [7] was issued on October 24, 1975, and validated over the range 0.13 to 0.4 mg/m* for a 180-1 air sample, using generated atmospheres of lead nitrate [2]. Recovery in the range 18 to 72 yg Pb per sample was 961, and collection efficiency of 0.8-ym mixed cellulose ester filters (Millipore Type AA) was 1001 for the aerosols. Subsequent studies on analytical recovery of 200 yg Pb per sanple gave the results [3,9]: Soecies Oioestion Method Analytical Recovery. 1 Pb metal Pb metal PbO PbS PbOj PbO; Pb in paint* Pb in paint* HNO3 00^ HNO3 H2O2 HNO3 on1y HNO3 only HNO3 only HNO3 H2O2 HNO3 only WO3 H2O2 92 + 4 7103 3 93 + 4 93 + 5 82 + 3 100 + 1 95 + 6 95 7 6 Standard Reference Material #1579, U.S. National Bureau of Standards. 2/15/84 7082-3 21574166 BFG15470 LEAD HETHOO: 7QB2 Additional collection efficiency studies Mere also done using Gelman GN-4 filters for the collection of Pb fine, which had geometric mean diameter of 0.1 in [3]. Mean collection efficiency for 24 sanpling runs at flow rates between 0.15 and 4.0 l/min was >97 + 21. Overall precision, sP, was 0.072 for lead nitrate aerosol [2,7] and 0.068 for Pb fine [3,9]. REFERENCES: [1] Criteria for a Recomnended Standard...Occupational Exposure to Inorganic lead (Revised Criteria), U.S. Department of Health, Education, and Welfare, Publ. (NI0SH) 78-158 (1978). [2] Documentation of the NIOSH Validation Tests, U.S. Department of Health, Education, and Welfare. Publ. (NIOSH) 77-18S (1977). [3] Heavy fetal Aerosols: Collection and Dissolution Efficiencies, Final Report of NIOSH Contract 210-79-0058, W. F. Gutknecht, H. H. Ranade, P. H. Grohse, A. Damle, and 0. O'Neal, Research Triangle Institute; available as Order No. PB 83-106740 from NTis, Springfield, VA 22161 (1981). [4] NIOSH Manual of Analytical Methods, 2nd. ed., V. 1, PCCAM 102, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77-157-A (1977). [5] Ibid. P&CAM 191. [6] Ibid. P4CAM 214. [7] Ibid., V. 3, S341, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77--157--C (1977). [8] Ibid. V. 5, PACAM 173, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77-157-A (1979). [9] Ibid, V. 7, S341 (revised 3/25/81), U.S. Department of Health and Hunan Services, Publ. (NIOSH) 82-100 (1962). [10] Analytical Methods for Atomic Absorption Spectrophotometry, Perkin-Elmer (1976). METHOD REVISED BY: Mark Hillson and R. Delon Hull, NIOSH/DPSE; S341 originally validated under NIOSH Contract CDC-94-74-4S; additional studies under NIOSH Contract 210-79-0058. 2/15/84 7062-4 BFG15471 5. Hydrochloric Acid NIOSH - 7903 BFG15472 1574168 INORGANIC ACIDS Methods Research Branch Analytical Method Analyte: Matrix: Procedure: Inorganic acids (Table I) Air Silica gel tube collection, eluent desorption, ion chromatography Method No.: Range: Precision: P&CAM 339 Table I 0.06-0.10 Date Issued: 8/18/81 Date Revised: Classification: D (Operational) 1. Synopsis 1.1 A known volume of air is drawn through a silica gel sampling tube to collect the analyte. The samples are desorbed in an aqueous solution of 0.003 M NaHC03/0.0024 M Na2C03 with heat. Solutions of samples and standards are analyzed by means of an ion chromatograph. 2. Working Range, Sensitivity, and Detection Limit 2.1 For H3PO4, H2SO4, HNO3, and HBr, the working range is based on a 4o-L air sample and on a 15-L air sample for HC1. Refer to Table I. 2.2 The sensitivity is expressed as yg per sample per mm chart deflection at a conductance setting of 10 imhos full scale. 2.3 With a 10-mL final solution volume and the instrumental parameters stated in the method, the lowest analytically quantifiable level (LAQl) is stated as u9/sample at 10% relative standard deviation. This lower limit may be extended through use of a more sensitive conductivity meter setting. 339-1 3. Interferences 3.1 Possible interferences in the method are SO2 for H2SO4 and NO2 for HNO3. Their collection potential on silica gel and reduction during desorption have not been investigated. 3.2 Chlorine or hypochlorite ion may interfere with chloride up to 50% of its initial concentration, and bromine may give an interference of approximately 30% of its original concentration as determined from spiked samples. The collection potential of these substances on silica gel has not been investigated. 4. Precision and Accuracy 4.1 The precision is expressed as percent relative standard deviation for the overall sampling and analytical method over the range stated for each acid (Table I). 4.2 The collection efficiencies for each of the acids are based on samples at three concentration levels, 0.2, 1 and 2 times the OSHA permissible exposure limits. 5. Advantages and Disadvantages 5.1 The advantage of ion chromatography over other methods is its capability of separating the ions such that each of the acid anions may be identified and measured in a single sample. 5.2 The method is specific for the acid anions. Different oxidation states of the acids have different retention times, e.g., NOJ, NO3, SO32, SO32. 5.3 The sampling device is a solid sorbent collection tube and involves no liquids. 5.4 The sampling device will collect five inorganic acids in both particulate and vaporous forms. 5.5 Because identification is based on retention time, interferences may not be easily identified. 6. Apparatus 6.1 Air Sampling Equipment 6.1.1 Personal sampling pumps capable of operation at 0.2 L/min and calibrated to an accuracy of 5% with a representative sampling tube in line. OZTtZ&?Z 339-2 \` 6.1.2 Silica gel tubes. 7-mm o.d./4.8 mm i.d. glass tubes approximately 10 cm in length packed with 400 mg of 20/40 mesh washed silica gel in the front section and 200 mg in the backup section. Polyurethane foam plugs are placed between the sorbent sections and at the end. The front section of silica gel is held in place with a 5-mm diameter plug of thick glass fiber filter. The silica gel is washed by the following procedure: Approximately a 200-mL volume of silica gel is placed in a 1-L beaker. 500-600 mL of deionized water is added slowly with stirring. When the exothermal reaction has subsided, the silica gel is heated in a 100 C water bath for approximately 30 minutes with occassional stirring, decanted, and rinsed four to five times with deionized water. It is heated again in deionized water for 15-30 minutes, decanted, and rinsed thoroughly with deionized water. The silica gel is then dried overnight in a 100 C oven until free flowing. If a blank of the silica gel shows any impurities, the washing procedure is repeated. Approximately 90% of the resulting silica gel will be 20/40 mesh. 6.1.3 Barometer. 6.1.4 Thermometer. 6.1.5 Hygrometer. 6.1.6 Stopwatch. 6.2 Ion chromatograph with a standard or fast run anion precolumn and separator column, a standard suppressor column, and conductimetric detector (Oionex Corp., Sunnyvale, CA, or equivalent). 6.3 Strip chart recorder. 6.4 Electronic integrator or some other suitable means of determining peak height (optional). 6.5 Centrifuge tubes, 15-mL, graduated. 6.6 Micropipettes with disposable tips forpreparing standards. 6.7 Volumetric flasks, 100-mL and25-mL or otherconvenient sizes for preparing standard solutions. 6.8 Syringes, 10-mL, polyethylene with luer tip. 339-3 W W BFG15475 6.9 6.10 6.11 In-line filter holders (Swlnnex-type) with 25-mm membrane filters, 0.8 pore size, or Acrodisc in-line filters. Parafilm. Water bath maintained at 100 C. 7. Reagents Whenever possible, reagents used should be ACS reagent grade or better. 7.1 Deionized, filtered water. Conductivity grade deionized water with specific conductance of 10 imho/cm or less is needed for the preparation of eluents and other solutions used in the ion chromatograph. The water must be filtered before use to avoid plugging valves in the chromatograph. 7.2 Silica gel, 3/8 mesh, grade 01, thoroughly washed with deionized water (Sec. 6.1.2). 7.3 Sodium carbonate, Na2C03. 7.4 Sodium bicarbonate, NaHC03. 7.5 Potassium chloride, KC1. 7.6 Monopotassium phosphate, KH2PO4. 7.7 Potassium sulfate, K2SO4. 7.8 Sodium nitrate, NaN03* 7.9 Sodium bromide, NaBr. 7.10 Stock standard solutions (1000 yg/mL). Dissolve salt in deionized, filtered water in a 100-mL volumetric flask, and dilute to volume with deionized, filtered water. 7.10.1 7.10.2 7.10.3 Chloride (1000 ppm Cl"). Dissolve 0.2103 g KC1/100 mL. Phosphate (1000 ppm P0$3). Dissolve 1.433 g KH2PO4/IOO mL. Sulfate (1000 ppm SO32). Dissolve 0.1814 g K2SO4/IOO mL. 7.10.4 Nitrate (1000 ppm NO3). Dissolve 0.13707 g NaN03/100 mL. 339-4 BpG 15476 7.10.5 Bromide (1000 ppm Br~). Dissolve 0.1288 g NaBr/100 mL. 7.11 Eluent (0.003 M NaHC03/0.0024 M Na2C03). Dissolve 1.008 g NaHC03 and 1.0176 g Na2C03 in 4 L of deionized, filtered water. 8. Procedure 8.1 Cleaning of Equipment. Glassware and plasticware should be washed in detergent and thoroughly rinsed with deionized water. Acid cleaning is not recommended. 8.2 Collection and Shipping of Samples 8.2.1 Each personal sampling pump must be calibrated with a representative collection tube in line to assure accurately known sample volumes. 8.2.2 Immediately before sampling, break the ends of the collection tube to provide an opening of at least one half of the internal diameter of the tube. 8.2.3 Insert the tube in the sampling device with the glass fiber filter plug at the inlet. Place tube in a vertical position during sampling to minimize channeling through the sorbent. 8.2.4 Collect the sample at 0.2 Lpm. The air being sampled should not pass through any hose or tubing before entering the collection tube. A sample size of 48-L is recommended. 8.2.5 Record the temperature, relative humidity, and pressure of the air being sampled. If the pressure reading is not available, record the elevation. 8.2.6 After sampling, label the collection tubes appropriately and cap the ends with plastic caps. 8.2.7 With each batch of up to 10 samples submit one blank collection tube which has been subjected to the same handling except that no air has been drawn through it. 8.3 Analysis of Samples 8.3.1 Place the silica gel and glass fiber plug from the front section of the collection tube into a 15-ml graduated centrifuge tube. (The backup section is analyzed separately.) to 339-5 CZ.TW.ST BFG15477 8.3.2 8.3.3 Add 5-6 mL of eluent solution (Section 7.7) and heat in a 100 C water bath for 10 minutes. Allow to cool and dilute to a 10-mL volume with eluent. Cover with Parafilm and shake vigorously. Pour the contents into a 10-mL plastic syringe fitted with an in-line filter and collect the filtrate in a second syringe or autosampler vial. 8.3.4 Inject 100-jJ_ aliquots of the filtered sample into the ion chromatograph and record the sample identity and instrumental conditions. Typical operating conditions for inorganic acids are: Eluent: Flow Rate: Columns: Conductivity Meter Setting: Injection Volume: Recorder Speed: 0.003 M NaHC03/0.0024 M N32C03 138 ml/hr (30% pump capacity) Standard Anion precolumn Standard Anion separator Standard Anion suppressor 10 ynho full scale 100 U30 cm/hr. 8.3.5 Measure and record peak height of each peak. The use of peak height is recommended over peak area for ion chromatography. 9. Calibration and Standardization 9.1 From the 1000 yg/mL acid stock solutions in Section 7.10, prepare mixed working standards in the concentrations of 0.5, 1, 2, 5, 10, 15, and 20 ug/mL in eluent solution (Section 7.7). The use of eluent eliminates the water dip in the chromatogram which occurs immediately before the elution of the chloride peak. These standards should be prepared fresh weekly and stored in polyethylene bottles. 9.2 With eacn set of samples analyzed, a complete calibration curve should be constructed. Plot peak height versus concentration. 10. Calculation 10.1 Read the concentration of each sample and blank from the calibration curve obtained in Section 9.2. Calculate the net concentration of each acid anion found C] C2 - B 339-6 BFG15478 10.2 where: C-j * acid anion concentration from air sample (yg/mL) C-2 3 total acid anion found on silica gel tube (ug/mL) B * acid anion concentration from blank (ig/mL). Calculate the concentration of acid in air sample. 10.2.1 Acid concentration in mg/m3 where: F C1 D CA V CA acid concentration in air (mg/m3) Cl anion concentration in solution (yg/mL) 0 final volume of desorbed sample (mL) V volume of air sampled (L) F factor for converting anion to acid. Acid F H3PO4 H2S04 HN03 HBr HC1 1.032 1.021 1.016 1.0125 1.028 10.2.2 Vapor-forming acid concentration in ppm. One gram molecular weight of a gas occupies 24.45 L at 25 #C and 760 mm Hg pressure CB = K x CA x 760 x T 298 x P where: Cg 3 acid concentration in air (ppm) CA = acid concentration in air (mg/m3) T = absolute temperature at which the sample was taken (K = C + 273) P = air pressure at which the sample was taken (mm Hg). K * vol. acid g-mol. wt. acid Acid K HNO3 HBr HC1 0.3881 0.3022 0.6699 f it t <i 21574175 339-7 BFG15479 t\ci crences 11.1 Cassinelli, M. E. and Taylor, D. G., Monitoring for Airborne Inorganic Acids, Symposium on Measurement and Control of Chemical Hazards in the Workplace Environment, ACS Symposium Series (1980). 11.2 Cassinelli, M. E., Ion Chromatographic Determination of Hydrogen Chloride - Hydrogen Bromide Mixtures, IMDS, MRB, Technical Report (1979). Mary Ellen Cassinelli Inorganic Methods Development Section 339-8 W CA $ h4 BFG15480 Appendix D Calibration Sampling Equipment BFG15481 APPENDIX D Calibration of Sampling Equipment (OSHA Procedure (8), Industrial Hygiene OSHA Technical Manual, 1990) 1. Procedures for Calibration of Pump-Collector Tube System (Organic Vapor Collection ) -Using Electronic Bubble Meter Method: (1) Allow the pump to run 5 minutes prior to voltage check and calibration. (2) Assemble the charcoal tube holder, using the appropriate tube for the sampling method. Compress charcoal tube by using a mechanical press or other means of applying pressure. Use shrink tape around charcoal tube to cover joints and prevent leakage. If a tube adaptor is using , care should be taken to ensure that it does not come in contact with the back-up pad. NOTE : When calibrating with a bubble meter , the use of tube adaptors can cause moderate to severe pressure drop at high flow rates in the sampling train, which will affect the calibration result. If adaptors are used for sampling , then they should be used when calibrating. CAUTION: Nylon adapters can restrict air flow due to plugging over time.Stainlesssteel adapters are preferred. (3) Connect the collection device, tubing, pump and calibration apparatus as shown in Figure 1 and 2 charcoal tube and cyclone samplers^ respectivel,y. UT 574178 1 BFG15482 (4) A visual inspection should be made of all Tygon tubing connections. (5) Wet the inside of the electronic flow cell with the supplied soap solution by pushing on the button several times. (6) Turn on the pump and adjust the pump rotameter, if available, to the appropriate flow rate setting. (7) Press the button on the electronic bubble meter. Visually capture a single bubble and electronically time the bubble . The accompanying printer will automatically record the calibration reading in liters per minute. (8) Repeat step 7 until two reading are within 5% . (9) Repeat the procedures described above for all pumps to be used for sampling. The same charcoal tube may be used for all calibrations involving the same sampling methods. Procedure for Calibration of Pump-Cassette Filter System ( Particulate - total dust). --Using Electronic Bubble Meter Method: (1) Allow the pump to run 5 minutes prior to voltage check and calibration. (2) Assemble the polystyrene cassette filter holder, using the appropriate filter for the sampling method. Compress cassette by using a mechanical press or other means of applying pressure. Use shrink tape around cassette to cover joints and prevent leakage. If a cassette adaptor is using, care should be taken to ensure that it does not come JO 2 BFG15483 1574179 in contact with the back-up pad. NOTE : When calibrating with a bubble meter t the use of cassette adaptors can cause moderate to severe pressure drop at high flow rates in the sampling train, which will affect the calibration result. If adaptors are used for sampling , then they should be used when calibrating. CAUTION: Nylon adapters can restrict air flow due to plugging over time. Stainless steel adapters are preferred. (3) Connect the collection device, tubing, pump and calibration apparatus as shown in Figure 1 and 2 cassette and cyclone samplers, respectively. (4) A visual inspection should be made of all Tygon tubing connections (5) Wet the inside of the electronic flow cell with the supplied soup solution by pushing on the button several times. (6) Turn on the pump and adjust the pump rotameter, if available, to the ij appropriate flow rate setting. (7) Press the button on the electronic bubble meter. Visually capture a single bubble and electronically time the bubble . The accompanying printer will automatically record the calibration reading in liters per minute. (8) Repeat step 7 until two reading are within 5% . (9) Repeat the procedures described above for all pumps to be used for sampling. The same cassette and filter may be used for all calibrations involving the same sampling methods. ^ l/T rfc> h* 09 BFG15484