# Elements by Cellulosic Internal Capsule Sampler (7306)

​ELEMENTS by Cellulosic Internal Capsule Sampler AW: Table 1
CAS: Table 2
METHOD: 7306, Issue 1 OSHA PELs: NIOSH RELs: OTHER OELs:
EVALUATION: FULL
cadmium calcium chromium cobalt copper
indium iron lanthanum lead lithium
magnesium manganese molybdenum nickel phosphorus
potassium selenium silver strontium tin
SAMPLING SAMPLER: Internal capsule, cellulose acetate dome with inlet opening, attached to 0.8-μm pore size mixed cellulose ester (MCE) membrane filter and housed within a 2-piece, closed-face cassette (CFC) filter holder, 37-mm diameter
FLOWRATE: 1 to 4 L/min VOL-MIN: -MAX:
Table 1 Table 1
Issue 1: 10 September 2015
tellurium thallium titanium tungsten vanadium
yttrium zirconium zinc
MEASUREMENT
TECHNIQUE:
INDUCTIVELY COUPLED PLASMA – ATOMIC EMISSION SPECTROMETRY (ICP-AES)
ANALYTES:
Elements above
SAMPLE DISSOLUTION:
Hotplate digestion (NIOSH 7300 or 7301), microwave digestion (NIOSH 7302) or hot block extraction (NIOSH 7303) Dependent upon sample preparation method
WAVELENGTH:
Depends upon element; See Table 3
Minimum of 2 field blanks per set
BACKGROUND CORRECTION:
Spectral wavelength shift
ACCURACY
CALIBRATION:
Elements in acid matrix-matched to the sample; varies depending on sample preparation method
RANGE:
Varies with element
SAMPLE STABILITY: Stable
RANGES STUDIED:
Tables 3 and 4
BIAS:
Table 4
OVERALL PRECISION (ŜrT) Table 4 ACCURACY:
SOLUTION:
SHIPMENT: Routine
BLANKS:
RTECS: Table 2
PROPERTIES: Table 1
Table 2 Table 2 [1,2]
ELEMENTS: aluminum antimony arsenic
barium beryllium
7306
Table 4
ESTIMATED LOD: Table 3 PRECISION ( Sr ): Table 4
APPLICABILITY: The working range of this method is 4 x 10-5 mg/m3 to 10 mg/m3 for each element in a 500-L air sample. This is simultaneous elemental analysis, not compound specific. Verify that the types of compounds in the samples are soluble with the dissolution procedure selected. Some compounds of these elements require special sample treatment. INTERFERNCES: Spectral interferences are the primary interferences encountered in ICP-AES analysis. These are minimized by judicious wavelength selection, interelement correction factors and background correction [3,4]. OTHER METHODS: The internal capsule sampler used in this method is a recommended alternative to filter-only sampling [5] of NIOSH methods 7300 [6], 7301 [7], 7302 [8] and 7303 [9]. Use of an internal capsule sampler is an efficient means to account for sampler wall deposits that would otherwise be excluded by filter-only sampling. Unless other means are used to account for non-filter deposits inside the cassettes (e.g. within-cassette extraction, rinsing or wiping), internal capsule samplers should be used. OSHA method ID-125G [10] describes ICP-AES multielement analysis after hotplate digestion using nitric acid, sulfuric acid and hydrogen peroxide. ASTM D7035 [11] and ISO 15202 [12] are related voluntary consensus standard ICP-AES methods for multielement sampling and analysis of workplace atmospheres.
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 2 of 11
REAGENTS: 1. 2. 3. 4. 5.
6. 7.
EQUIPMENT:
Nitric acid (HNO3)*, concentrated, Trace metal grade Hydrochloric acid (HCl)*, conc., Trace metal grade (only required if hydrochloric acid digestion is to be carried out) Perchloric acid (HClO4)*, conc., optima (only required if perchloric acid digestion is to be carried out) Calibration stock solutions, 1000 μg/L: Commercially available; or prepared per instrument manufacturer’s recommendation Dilution acid: 20% nitric acid* (7302); 4% nitric acid:1% perchloric acid* (7300); 5% aqua regia (7301)*; or 5% nitric acid: 5% hydrochloric acid* (7303) [dilution acid is dependent upon sample preparation method used] Argon, as specified by ICP-AES manufacturer Deionized water, ASTM Type II [13] or equivalent
1.
Sampler: cellulose acetate internal capsule attached to mixed cellulose ester membrane filter, 0.8-μm pore size; 37-mm diameter, in 2-piece, closed-face cassette filter holder 2. Personal sampling pump, 1 to 4 L/min, with flexible connecting tubing, capable of maintaining constant flow 3. Inductively coupled plasma-atomic emission spectrometer, equipped as specified by the manufacturer for analysis of elements of interest 4. Regulator, two-stage, for argon 5. Beakers, Phillips, 125-mL, or Griffin, 50-mL, with watch glass covers** 6. Volumetric flasks, 10-, 25-, 100-mL, and 1-L** 7. Assorted volumetric pipets, as needed** 8. Forceps, plastic or plastic-tipped 9. Hotplate (NIOSH 7300 or 7301), microwave oven (NIOSH 7302) or hot block (NIOSH 7303) [6-9]. 10. Centrifuge tubes, 50-mL or sized appropriately for hot block apparatus.
rinse thoroughly in deionized water before use
SPECIAL PRECAUTIONS: All perchloric acid digestions must be carried out in a perchloric acid fume hood. When working with concentrated acids, wear protective clothing, safety goggles and gloves. All work should be performed with adequate ventilation for personnel and equipment. It is imperative that acid be added to water in order to avoid a violent exothermic reaction. SAMPLING: 1.
Calibrate each personal sampling pump with a representative sampler in line. NOTE: See NMAM guidance chapters for discussion on sampling. 2. Sample at an accurately known flow rate between 1 and 4 L/min (± 5%) for a total sample size of <1 to 2000 L (see Table 1) for TWA measurements. Do not exceed a sampler loading of approximately 5 mg total dust. NOTE: Filter overloading can be assessed by periodic visual checks. See NMAM guidance chapters for additional discussion on filter capacity. SAMPLE PREPARATION: 3.
Open the cassette filter holders and, using nonmetal forceps, transfer the samples and blanks to clean digestion vessels. NOTE: Samples may not easily fit into the digestion vessels. Care must be taken to ensure no sample is lost during the placement of the samples in the digestion vessels.
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 3 of 11
4. Carry out sample dissolution in accordance with one of the sample preparation procedures described in NIOSH 7300, 7301, 7302, or 7303 [6-9].
NOTE: The dissolution acid level within the vessel should cover the internal capsule. 5. After allowing to cool to room temperature, transfer the solutions quantitatively to 25-mL volumetric flasks. 6. Dilute to volume. NOTE: If greater sensitivity is required, the final sample volume may be held to 10 mL. CALIBRATION AND QUALITY CONTROL: 7. Calibrate the spectrometer according to the manufacturer recommendations. NOTE: Typically, an acid blank and 1.0 μg/mL multielement calibration standards are used.  The following multielement combinations are chemically compatible in 5% HNO3: a. Al, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, La, In, Na b. Ag, K, Li, Mg, Mn, Ni, P, Pb, Se, Sr, Tl, V, Y, Zn, Sc c. Mo, Sb, Sn, Te, Ti, W, Zr 8. Analyze at least one calibration standard per ten samples. 9. Check recoveries with at least one media blank and two spiked media blanks per twenty samples. Media should be spiked with analytes of interest. NOTE: Whenever possible, QA/QC samples should be prepared from certified reference materials in a matrix similar to the bulk material sampled. Liquid spiked filters are only surrogates for real world samples and QC data based upon certified samples are preferred. MEASUREMENT: 10. Set ICP-AES spectrometer to conditions specified by manufacturer. 11. Analyze standards and samples by ICP-AES in accordance with manufacturer recommendations. NOTE: If the values for the samples are above the range of the standards, dilute the solutions (ensuring
the samples remain acid matrix-matched to the calibration standards), reanalyze and apply the appropriate dilution factor in the calculations. CALCULATIONS: 12. Obtain the solution concentrations for the sample, Cs (μg/mL), and the average media blank , Cb (μg/mL), from the instrument. 13. Using the solution volumes of sample, Vs (mL), and media blank, Vb (mL), calculate the concentration, C mg/m3), of each element in the air volume sampled, V (L):
C=
(Cs Vs )-(Cb Vb ) V
, mg/m3
NOTE: μg/L Ξ mg/m3 EVALUATION OF METHOD: A previous interlaboratory investigation of aerosol-loaded cellulosic capsules (provided by SKC, Inc., EightyFour, PA) provided the background information for the development of this method [14]. That investigation yielded data for Cd, Cr, Co, Cu, Fe, Mn, Ni and Pb [14]. Recoveries for these elements were quantitative and values of overall relative standard deviation were <0.20 [14], which compare favorably with the variability typically observed in interlaboratory multielement analysis of air samples [15,16]. To obtain performance data for additional elements, interlaboratory performance data were obtained using 37-mm diameter cellulose acetate internal capsules attached to mixed-cellulose ester filters (Solu-sert™ from NIOSH Manual of Analytical Methods (NMAM), Fifth Edition ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 4 of 11
Zefon International, Ocala, FL). Solu-sert™ capsules were dosed with 33 elements at three different spiking levels (spike levels certified by High-Purity Standards, North Charleston, SC), listed in Table 3. Sets of the spiked samples were conveyed to participating volunteer laboratories and analyzed by ICP-AES after sample dissolution. A variety of sample preparation procedures were used by the labs including NIOSH 7300, 7301, 7302, 7303, hot plate digestion utilizing nitric acid, sulfuric acid and hydrogen peroxide (modified NIOSH 7300), and microwave assisted digestion using nitric acid and hydrogen peroxide (modified NIOSH 7302). Results were received from 9 laboratories; however, not every spiked element was reported by each laboratory. Individual sample results may be found in the backup data report [17]. Statistical calculations were performed using SAS Software (version 9.2, SAS Institute Inc., Cary, NC). For each data subset, Grubbs’ test at 1% confidence level was used to identify outliers, which if identified, were removed prior to further statistical calculations. No statistically significant differences were found between the laboratory results for the spiked samples; therefore, all reported data (regardless of the sample preparation method) are included in Tables 3 & 4. Recoveries were quantitative (as defined in Kennedy, et al. [18]) and interlaboratory variability was <0.20 for most elements and loading levels (Table 3). Mean overall recoveries below 90% were found only for Cr, K, and W at low loadings and for Ag at medium and high spike levels and for In at the high spike level. RSD values > 0.20 were found only for Sn at the low spike level, Ag at medium and high spike levels, and In and K at all loadings. Results for precision, bias and accuracy are summarized in Table 4. With the domed top, the internal capsule can be difficult to fit into standard sample digestion vessels. One way to achieve this is to place the samplers into the vessels by bending them slightly inward (using coated forceps) and to push them into the bottom of the vessel to ensure they are covered with the digestion acids. Care must be taken to ensure that sample is not lost in this process. Additional guidance is available from the internal capsule manufacturer [19]. While no statistically significant differences were found based upon the sample preparation, it is important to note that interlaboratory variation is included in those calculations. Some differences in the sample preparation methods may have been statistically significant without that variability. Of particular importance are the less than quantitative recoveries for Sb, Sn, and Ti using NIOSH 7300. This sample preparation (as written) may not be amenable to the analysis of those elements. While this method lists several options for sample preparation, it is imperative that the suitability of the particular sample preparation method for the analytes of interest be considered. Appreciable (>0.5 µg) media background levels were reported by Certified Reference Material (CRM) provider and/or the participating laboratories for several elements, notably Al, Ca, Cr, Fe, In, K, Mg, P, Sb, Se, and Tl. Trace media background levels of a few other elements, i.e., Ba, Cu and Zn, were also obtained. This background was effectively corrected for, as evidenced by the quantitative recoveries obtained for the vast majority of the elements and loading levels. Where the background levels may pose a greater influence is in the calculation of the method LOD. Method LODs (calculated using the standard deviation of blank responses) for internal capsule samples were greater than those calculated for MCE filters alone for many of the elements [17]. Care should be taken in choosing the appropriate media in concert with the expected sample concentrations. REFERENCES: ACGIH [2014]. TLVs and BEIs based on the documentation of the Threshold Limit Values for chemical substances and physical agents and biological exposure indices. Cincinnati, Ohio: American Conference of Governmental Industrial Hygienists [www.acgih.org]. Date accessed: May 2015. [2] Institut fur Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung [2013]. GESTIS database on hazardous substances (German Social Accident Insurance). Sankt Augustin, FRG: [1]. Date accessed: May 2015.
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 5 of 11
[3] Dean JA [1995]. Atomic spectroscopy. In: Analytical Chemistry Handbook; Section 7. New York, NY: McGraw-Hill. [4] Montaser A, Golightly DW, eds. [1992]. Inductively coupled plasmas in analytical atomic spectrometry. 2nd ed. Hoboken, NJ: John Wiley & Sons, Inc. [5] Ashley K, Harper M [2013]. Closed-face filter cassette (CFC) sampling – Guidance on procedures for inclusion of material adhering to internal sampler surfaces. J Occup Environ Hyg 10:D29-D33. [6] NIOSH [1994]. Elements by ICP (Nitric/Perchloric Acid Ashing): Method 7300. In: Schlecht PC, O’Connor PF, eds. NIOSH manual of analytical methods. 4th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113 [www.cdc.gov/niosh/ nmam/]. [7] NIOSH [1994]. Elements by ICP: Method 7301. In: Schlecht PC, O’Connor PF, eds. NIOSH manual of analytical methods. 4th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113 [www.cdc.gov/niosh/nmam/]. [8] NIOSH [2014]. Elements by ICP (Microwave Digestion): Method 7302. In: Ashley K, O’Connor PF, eds. NIOSH manual of analytical methods. 5th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2014-151 [www.cdc.gov/niosh/nmam/]. [9] NIOSH [1994]. Elements by ICP (Hot Block/HCl/HNO3 Digestion): Method 7303. In: Schlecht PC, O’Connor PF, eds. NIOSH manual of analytical methods. 4th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113 [www.cdc.gov/niosh/ nmam/]. [10] OSHA [2002]. Metal and metalloid particulates in workplace atmospheres (ICP analysis). In: OSHA Sampling and Analytical Methods. Sandy, UT: Occupational Safety and Health Administration. [11] ASTM International [2010]. ASTM D7035, Standard test method for the determination of metals and metalloids in workplace air by inductively coupled plasma atomic emission spectrometry. West Conshohocken, PA: ASTM International. [12] ISO [2011]. ISO 15202, Workplace air – Determination of metals and metalloids in airborne particulate matter by inductively coupled plasma atomic emission spectrometry (3 parts). Geneva, Switzerland: International Organization for Standardization. [13] ASTM [2011]. ASTM D1193, Standard specification for reagent water. West Conshohocken, PA: ASTM International. [14] Harper M, Ashley K [2013]. Acid-soluble internal capsules for closed-face cassette elemental sampling and analysis of workplace air. J Occup Environ Hyg 10:297-306. [15] Ashley K, Shulman SA, Brisson MJ, Howe AM [2012]. Interlaboratory evaluation of trace element determination in workplace air samples by inductively coupled plasma mass spectrometry. J Environ Monit 14:360-367. [16] Stacey P, Butler OT [2008]. Performance of laboratories analysing welding fume on filter samples – Results from the WASP Proficiency Testing Scheme. Ann Occup Hyg 52:287-295. [17] Ashley K, Andrews RN, Feng HA [2014]. Elements by cellulosic internal sampler and ICP-AES, NIOSH 7306, Backup Data Report. Cincinnati, OH, Unpublished. [18] NIOSH [1995]. Guidelines for air sampling and analytical method development and evaluation. By Kennedy ER, Fischbach TJ, Song R, Eller PM, Shulman SA. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 95–117. [19] Zefon International. Operating instructions Solu-Sert™ soluble filter capsule. Ocala, FL: Zefon International. Date accessed: May 2015.
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 6 of 11
[20] NIOSH [1994]. Measurement uncertainty and NIOSH method accuracy: Chapter P. In: Schlecht PC, O’Connor PF, eds. NIOSH manual of analytical methods. 4th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113 [www.cdc. gov/niosh/nmam/]. [21] Lide DR [2014]. Handbook of Chemistry and Physics, 94th ed. Boca Raton: FL, CRC Press [22] NIOSH [2005]. NIOSH pocket guide to chemical hazards. Barsan ME, ed. Cincinnati, OH: US Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2005-149. [www.cdc. gov/niosh/npg]. METHOD WRITTEN BY: Kevin Ashley, Ph.D., Ronnee N. Andrews, Ph.D., and H. Amy Feng, NIOSH/DART. Disclaimer: Mention of any company or product does not constitute endorsement by the National Institute for Occupational Safety and Health. In addition, citations to Web sites external to NIOSH do not constitute NIOSH endorsement of the sponsoring organizations or their programs or products. Furthermore, NIOSH is not responsible for the content of these Web sites. All Web addresses referenced in this document were accessible at the time of publication.
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 7 of 11
TABLE 1. PROPERTIES AND SAMPLING VOLUMES [21] Volume, L @ OSHA PELA Atomic Weight MINB MAXC Element (Symbol) (AW) MP, °C Silver (Ag) 107.87 961 6 >2000D Aluminum (Al) 26.98 660 <1 330 Arsenic (As) 74.92 817 32 >2000 Barium (Ba) 137.34 727 3 >2000 Beryllium (Be) 9.01 1287 10 >2000 Calcium (Ca) 40.08 842 --Cadmium (Cd) 112.41 321 3 >2000 Cobalt (Co) 58.93 1495 <1 >2000 Chromium (Cr) 52.00 1907 1 >2000 Copper (Cu) 63.54 1083 <1 >2000 Iron (Fe) 55.85 1538 2 500 Indium (In) 114.82 156 8 >2000 Potassium (K) 39.10 64 --Lanthanum (La) 138.91 920 --Lithium (Li) 6.94 181 --Magnesium (Mg) 24.31 651 <1 330 Manganese (Mn) 54.94 1246 <1 1000 Molybdenum (Mo) 95.94 2623 <1 330 Nickel (Ni) 58.71 1455 2 >2000 Phosphorus (P) 30.97 44 9 >2000 Lead (Pb) 207.19 328 4 >2000 Antimony (Sb) 121.75 631 1 >2000 Selenium (Se) 78.96 221 2 >2000 Tin (Sn) 118.69 232 <1 >2000 Strontium (Sr) 87.62 777 --Tellurium (Te) 127.60 450 7 >2000 Titanium (Ti) 47.87 1668 --Thallium (Tl) 204.37 304 1 >2000 Vanadium (V) 50.94 1910 --Tungsten (W ) 183.85 3422 --Yttrium (Y) 88.91 1522 <1 >2000 Zinc (Zn) 65.37 419 --Zirconium (Zr) 91.22 1855 <1 1000 Exposure limits listed in Table 2. Min calculated using the method quantitation limits following NIOSH 7302 sample preparation. C Max calculated using 5 mg of sample collected. D Indicates that the calculated maximum volume is greater than the volume collected at the maximum flow rate (4 L/min) of the method for an 8-hour shift. A B
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 8 of 11
TABLE 2. EXPOSURE LIMITS, CAS#, RTECS [22] Element (Symbol) CAS # RTECS #
Exposure Limits OSHA PEL (mg/m3) NIOSH REL (mg/m3)
Silver (Ag) Aluminum (Al)
7440-22-4 7429-90-5
VW3500000 BD0330000
0.01 (dust, fume, metal) 15 (total dust) 5 (respirable)
Arsenic (As) Barium (Ba) Beryllium (Be) Calcium (Ca) Cadmium (Cd) Cobalt (Co) Chromium (Cr)
7440-38-2 7440-39-3 7440-41-7 7440-70-2 7440-43-9 7440-48-4 7440-47-3
CG0525000 CQ8370000 DS1750000 -EU9800000 GF8750000 GB4200000
Copper (Cu)
7440-50-8
GL5325000
Iron (Fe) Indium (In) Potassium (K) Lanthanum Lithium (Li) Magnesium (Mg) Manganese (Mn) Molybdenum (Mo)
7439-89-6 7440-74-6 7440-09-7 7439-91-0 7439-93-2 7439-95-4 7439-96-5 7439-98-7
NO4565500 NL1050000 TS6460000 -OJ5540000 OM2100000 OO9275000 QA4680000
Nickel (Ni) Phosphorus (P) Lead (Pb) Antimony (Sb) Selenium (Se) Tin (Sn) Strontium (Sr) Tellurium (Te) Titanium (Ti) Thallium (Tl) Vanadium (V)
7440-02-0 7723-14-0 7439-92-1 7440-36-0 7782-49-2 7440-31-5 7440-24-6 13494-80-9 7440-32-6 7440-28-0 7440-62-2
QR5950000 TH3500000 OF7525000 CC4025000 VS7700000 XP7320000 WK7700000 WY2625000 XR1700000 XG3425000 YW1355000
Tungsten (W) Yttrium (Y) Zinc (Zn)
7440-33-7 7440-65-5 7440-66-6
YO7175000 ZG2980000 ZG8600000
Zirconium (Zr)
7440-67-7
ZH7070000
0.010 0.5 0.002, C 0.005 -0.005 0.1 (dust, fume) 1 (metals, insoluble salts) 0.5 (Cr II & Cr III) 1 (dust, mists) 0.1 (fume) 10 (fume) as oxide 0.1 -– -15 (dust) as oxide C5 5 (soluble) 15 (total insoluble dust) 1 0.1 0.05 0.5 0.2 2 – 0.1 15 as dioxide 0.1 (skin) (soluble) C 0.5 (respirable) as pentoxide -1 5 (fume, respirable dust) as oxide 15 (total dust) as oxide 5
E
C: ceiling Ca: carcinogen G STEL: short-term exposure limit F
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition
0.01 (metal, soluble) 10 (total dust) 5 (respirable fume) 2 (soluble) CE 0.002 (15 min), CaF 0.5 C 0.0005, Ca -lowest feasible, Ca 0.05 (dust, fume) 0.5 1 (dust, mists) 0.1 (fume) 5 (dust, fume) oxide as Fe 0.1 -– --C 1; STELG 3 -0.015, Ca 0.1 0.05 0.5 0.2 2 – 0.1 Ca as the oxide 0.1 (skin) (soluble) C 0.05 as pentoxide 5; STEL 10 1 5 (dust, fume) as oxide C 15 (dust) as oxide STEL 10 (fume) as oxide 5; STEL 10 ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 9 of 11
TABLE 3. MEASUREMENT WAVELENGTHS (λ), DETECTION LIMITS (LOD) AND RECOVERY DATA FROM INTERLABORATORY RESULTS Element
Ag Al As Ba Be Ca Cd Co Cr Cu Fe In K La Li Mg Mn Mo Ni P Pb
WavelengthH (λ), nm
328.068 396.152 189.042 455.404 313.042 315.887 226.502 228.616 267.716 324.754 259.941 230.606 766.491 408.672 670.780 279.079 294.921 202.095 231.604 178.287 220.353
LODI (ug/sample)
0.020 0.38 0.099 0.55 0.0064 3.9 0.0052 0.0090 0.28 0.15 5.3 0.26 0.70 0.026 0.010 1.1 0.031 0.021 0.56 0.27 0.062
Low Level (ug/sample)
5.0 10.6 5.0 2.21 2.01 114 2.01 2.01 2.91 3.16 21.3 5.0 10.6 3.01 2.01 12.7 2.01 2.01 2.01 10.1 10.0
% Recovery (%RSD; NJ)
93.2 (17; 7) 95.7 (6.1; 7) 99.4 (7.3; 7) 97.0 (8.4; 8) 101 (4.4; 9) 95.8 (16; 8) 101 (3.6; 9) 103 (6.8; 9) 80.2 (16; 8) 100 (4.5; 8K) 107 (15; 9) 92.1 (33; 5) 89.0 (36; 5) 101 (8.1; 4) 93.0 (8.5; 7) 93.9 (16; 7) 99.8 (7.6; 9) 101 (6.2; 9) 108 (9.6; 9) 104 (9.0; 5) 101 (6.2; 9)
Medium level (ug/ sample)
10.1 30.9 20.2 7.3 7.0 165 7.0 7.0 7.9 15.1 41.0 14.9 15.7 10.1 7.0 27.9 7.0 7.1 7.0 24.9 25.2
% Recovery (%RSD; NJ)
83.5 (26; 7) 95.7 (3.1; 7) 103 (5.3; 8) 96.9 (2.5; 7K) 101 (6.8; 9) 97.4 (15; 8) 101 (4.0; 9) 102 (5.7; 9) 96.3 (7.2; 9) 101 (4.0; 9) 104 (5.5; 9) 90.8 (27; 5K) 98.0 (24; 6) 102 (7.2; 4) 94.9 (7.0; 7) 98.7 (9.1; 7) 100 (6.1; 9) 102 (4.8; 9) 104 (7.4; 9) 103 (8.9; 6) 100 (5.3; 9)
High Level (ug/ sample)
20.1 60.8 40.1 15.2 14.9 215 14.9 14.9 15.8 29.9 80.5 39.7 20.7 20.1 14.9 103 14.9 15.0 14.9 99 100
Commonly used wavelength; choose wavelength appropriate for your instrument settings [3,4] LOD values calculated using the responses of 7 media blanks, prepared following the microwave sample preparation in NIOSH 7302 J Mean recovery & relative standard deviation for N = number of laboratories reporting results for each element K Excludes outlier(s) (Grubbs’ test) H I
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition
% Recovery (%RSD; NJ)
68.2 (52; 7) 96.2 (2.4; 7) 102 (5.8; 8) 99.9 (5.0; 8) 100 (5.1; 9) 95.8 (13; 8) 102 (1.9; 8) 102 (5.8; 9) 97.2 (3.5; 9) 100 (3.2; 9) 103 (5.4; 9) 86.2 (32; 5) 106 (20; 6) 99.9 (7.9; 4) 98.6 (5.2; 7) 101 (7.2; 7) 100 (5.7; 9) 102 (5.2; 9) 103 (7.0; 9) 102 (1.7; 5K) 100 (7.3; 9) ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 10 of 11
Table 3 continued from page 9 TABLE 3. MEASUREMENT WAVELENGTHS (λ), DETECTION LIMITS (LOD) AND RECOVERY DATA FROM INTERLABORATORY RESULTS Element
Sb Se Sn Sr Te Ti Tl V W Y Zn Zr
WavelengthH (λ), nm
206.833 196.090 189.991 407.771 214.281 334.941 190.864 311.071 207.911 371.030 213.856 339.198
LODI (ug/sample)
0.11 0.14 0.065 0.014 0.22 0.042 0.046 0.0091 0.055 0.0039 0.69 0.0099
Low Level (ug/sample)
5.0 3.0 2.01 2.01 3.0 2.01 3.0 3.02 10.1 2.01 5.2 2.01
% Recovery (%RSD; NJ)
99.1 (6.7; 8) 112 (15; 6) 98.7 (26; 4) 100 (1.9; 6K) 104 (18; 5) 105 (5.7; 7) 102 (7.1; 6) 101 (5.7; 9) 83.0 (12; 5) 101 (3.8; 5) 101 (6.0; 9) 101 (6.2; 5)
Medium level (ug/ sample)
25.1 15.1 7.0 7.1 12.6 7.0 10.1 7.0 25.1 7.1 25.1 7.0
% Recovery (%RSD; NJ)
99.0 (5.7; 9) 109 (8.7; 8) 96.9 (18; 6) 102 (7.5; 7) 103 (7.7; 5) 101 (10; 7) 99.6 (5.8; 7) 102 (6.2; 9) 97.6 (12; 5) 102 (5.9; 5) 101 (4.9; 9) 99.5 (9.2; 6)
High Level (ug/ sample)
40.2 30.1 14.9 15.0 20.1 14.9 20.1 14.9 40.2 15.0 59.7 14.9
Commonly used wavelength; choose wavelength appropriate for your instrument settings [3,4] LOD values calculated using the responses of 7 media blanks, prepared following the microwave sample preparation in NIOSH 7302 J Mean recovery & relative standard deviation for N = number of laboratories reporting results for each element K Excludes outlier(s) (Grubbs’ test) H I
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition
% Recovery (%RSD; NJ)
100 (3.6; 8K) 104 (10; 8) 103 (5.0; 5K) 101 (6.1; 7) 101 (12; 5) 103 (3.4; 6K) 98.3 (7.5; 7) 102 (5.8; 9) 96.4 (16; 5) 101 (4.8; 5) 101 (4.8; 9) 93.1 (19; 6) ​ELEMENTS by Cellulosic Internal Capsule Sampler: METHOD 7306, Issue 1, dated 10 September 2015 - Page 11 of 11
TABLE 4. RANGE, BIAS, PRECISION (  Sr  and ŜrT) AND ACCURACY DATA FROM  INTERLABORATORY RESULTS Element nL Range, ug/sample Bias ŜrTN SrM
Accuracy (%)
Ag
21
5.0 to 20.1
-0.184
0.041
0.065
29.0
Al
21
10.6 to 60.8
-0.0414
0.006
0.050
12.4
As
23
5.0 to 40.1
0.0141
0.016
0.052
10.7
Ba
23
2.21 to 15.2
-0.0206
0.036
0.062
12.8
Be
27
2.01 to 14.9
0.00536
0.025
0.056
11.0
Ca
24
114 to 215
-0.0367
0.001
0.050
11.9
Cd
26
2.01 to 14.9
0.0133
0.022
0.055
11.1
Co
27
2.01 to 14.9
0.0238
0.036
0.062
12.9
Cr
26
2.91 to 15.8
-0.0281
0.046
0.068
14.4
Cu
26
3.16 to 29.9
0.00347
0.017
0.053
10.4
Fe
27
21.3 to 80.5
0.0476
0.011
0.051
13.2
In
15
5.0 to 39.7
-0.103
0.056
0.075
22.6
K
17
10.6 to 20.7
-0.0239
0.029
0.058
12.3
La
12
3.01 to 20.1
0.0119
0.025
0.056
11.2
Li
21
2.01 to 14.9
-0.0447
0.039
0.064
14.9
Mg
21
12.7 to 103
-0.0219
0.012
0.051
10.9
Mn
27
2.01 to 14.9
0.00127
0.039
0.063
12.4
Mo
27
2.01 to 15.0
0.0169
0.032
0.060
12.1
Ni
27
2.01 to 14.9
0.0498
0.055
0.074
17.2
P
16
10.1 to 99
0.0310
0.010
0.051
11.5
Pb
27
10.0 to 100
0.00439
0.006
0.050
9.9
Sb
25
5.0 to 40.2
-0.00631
0.013
0.052
10.2
Se
22
3.0 to 30.1
0.0864
0.055
0.075
20.9
Sn
15
2.01 to 14.9
-0.00541
0.117
0.128
25.0
Sr
20
2.01 to 15.0
0.00930
0.011
0.051
10.2
Te
15
3.0 to 20.1
0.0256
0.063
0.081
16.6
Ti
20
2.01 to 14.9
0.0305
0.032
0.059
13.1
Tl
20
3.0 to 20.1
0.00128
0.030
0.058
11.4
V
27
3.02 to 14.9
0.0143
0.020
0.054
10.9
W
15
10.1 to 40.2
-0.0240
0.010
0.051
11.0
Y
15
2.01 to 15.0
0.00971
0.020
0.054
10.7
Zn
27
5.2 to 59.7
0.00873
0.013
0.052
10.3
Zr
17
2.01 to 14.9
-0.0206
0.033
0.060
12.4
n = total number of results reported for each element by up to 9 participating laboratories minus outliers   (Grubbs’ test, 1% confidence level) L
M
N
Sr = precision [17] ŜrT = overall precision =
2
S r +(0.05)2 ; same as total precision as defined in [18,20]
NIOSH Manual of Analytical Methods (NMAM), Fifth Edition