Page:NIOSH Manual of Analytical Methods - 7603.pdf/2

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.

QUARTZ in coal mine dust: METHOD 7603, Issue 3, dated 15 March 2003 - Page 2 of 7 EQUIPMENT:

REAGENTS: 1. Qua rtz* (SRM 1878a, 295 0, 2951, 2958), available from Sta ndard R eference Mate rials Program, Rm. 204, Bldg. 202, National Ins titute of Stan dards T echnology, Gaithersbu rg, MD 2 0899; ww w.nist.gov. 2. 2-Propanol*, reagent grade. 3. Ca libration s tock solution, 15 µg/m L. Suspend 7.5 mg of quartz in 2-propanol in a 500-mL volumetric flask and dilute the suspension to the mark with 2-propanol (See CAL IBRAT ION A ND QU ALITY C ON TR OL). 4. Kaolinite (Hydrite UF from Geo rgia Kaolin), for standard samples, 100 µg/mL. Suspend 50 m g of dried kaolinite in a 500-m L volum etric flas k w ith 2-propa nol an d dilute the susp ens ion to the m ark with 2-prop ano l. NOTE: This is not required if muffle furnace is used to ash sam ples (see step 5). 5. Hydroch loric ac id solution*. 25% v/v conc. HCl in distilled wate r. Required if ca lcite is present and sam ples are ashed with a m uffle furnace. 6. Desicca nt (Drierite). 7. Oxygen, purified.

  • See SPECIAL PRECAUTIONS

1. Sam pler: a. Filter: 37-mm diameter, 5.0-µm pore size, polyvinyl chloride filter s upp orted with back up pad in a two-piece, 37-m m cassette filter ho lder (preferably, conductive) held together by tape or cellulose shrink band. b. Cyclone: 10-m m nylon or Higgins-Dew ell (HD ). c. Sam pling head holder: Holder must keep the cassette, cyclone and coupler together rigidly so that air enters only at the cyclone inlet. 2. Area air sampler: PVC m embrane filter, 37mm , 5-µm pore size in two-piece filter cassette . Sa m ple closed fa ce at 3 L/m in 3. Sam pling pumps for: HD cyclone, 2.2 L/min; nylon cyclone , 1.7 L/m in; and area sam pler, 3 L/min. 4. Filters for standards and redeposition, 47m m diam ete r, 0.45 -µm pore size , vinyl chloride-acrylonitrile copolymer m embrane (DM -450 G elma n Science s, or equivalent). 5. Glass fiber filters, 25-mm diameter, for backup during filtration. 6. Filtratio n apparatu s for red epositing sam ple after ashing, consisting of fritted support (Millipore XX1002502), side-arm vacuum flask and sp ecial funnel similar to Millipore XX1002514 but with an internal diameter of 1.0 cm . The fun nel is glass with a b akelite bas e an d sh ould sea l to the fritted sup port to m ake the fit liquid-tight.** 7. Funne l for treating filters to rem ove calcite (required only if using a m uffle furnace): Millipore XX1002514 with apparatus in item 6 above except with funnel internal diameter ca. 1.6 cm; 0.5-µm pore size PVC filters, 37m m diam eter to recollect residue .** 8. Doub le-beam infrared spectrophotom eter, with sam ple ho lders for infra red instrum ent: metal (preferably steel) plates with a center hole to m atc h the diam ete r of the sam ple dep osit (1 cm ), and sm all ring m agn ets to hold the filter in position on the plate. 9. Low-temperature radio frequency asher (LTA ) or m uffle furnace (600 °C ). 10. Ultrasonic bath. 11. Porc elain cruc ibles with cove rs, 10-m L.** 12. Bea kers , 50-m L.** 13. Analytical balance, 0.01-mg; desiccator cab inet. 14. Magnetic stirrer with thermally insulated top,

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition