Page:NIOSH Manual of Analytical Methods - 2550.pdf/2

 BENZOTHIAZOLE IN ASPHALT FUME: METHOD 2550, Issue 1, dated 15 January 1998 - Page 2 of 5 REAGENTS:

EQUIPMENT:

1. Sampler 1. Hexane,* chromatographic grade. a. Prefilter: PTFE-laminate membrane filter, 2. Benzothiazole,* reagent grade. 2-µm pore size, 37-mm, (Zefluor, 3. Benzothiazoleprimary stock solution, 10 mg/mL: Gelman Sciences, Ann Arbor, MI, or Dissolve 1.0 g benzothiazole in 100 mL of equivalent), backed by a gasket (37-mm hexane in a volumetric flask. (Correct for purity OD, 32-mm ID) cut from a cellulose support of standard.) pad or SKC #225-23, in cassette filter 4. Benzothiazole secondary stock solution, holder. 1 mg/mL: Dilute 1.0 mL of primary stock with NOTE: If sampling in bright sunlight, use hexane to 10 mL in a volumetric flask. opaque or foil-wrapped cassettes to prevent photodegradation. b. Solid sorbent: glass tube, 100 mm, 10-mm OD, sealed ends with plastic caps, containing two sections of washed XAD-2 resin (front = 100 mg; back = 50 mg), separated and retained with glass wool plugs (Supelco ORBO-42 Large or equivalent), connected to filter with minimum length PVC tubing. 2. Personal sampling pump capable of operating for 8 h at 2 L/min., with flexible connecting tubing. 3. Gas Chromatograph, autosampler, nitrogen chemiluminescence detector (Antek Model 704E, or equivalent), integrator, and column (Restek Rtx-1®, or equivalent)(page 2550-1) 4. Vials, glass, PTFE-lined screw caps, 5-mL. 5. Vials, Autoinjector, glass with PTFE-lined crimp caps, 1.8-mL. 6. Forceps. 7. Syringes, 5-, 10-µL, other sizes if needed. 8. Volumetric flasks, 10-mL, 100-mL. 9. Aluminum foil. 10. Refrigerant packs. 11. ORBO-43 sampling tubes (Supelco) SPECIAL PRECAUTIONS: Hexane is highly flammable. Benzothiazole has an irritating odor and is highly toxic by ingestion. Handle in a well ventilated hood and wear protective clothing.
 * See SPECIAL PRECAUTIONS

SAMPLING: 1. 2. 3. 4.

Calibrate each personal sampling pump with a representative sampler in line. Sample at an accurately known flow rate of 1.0 to 2.0 L/min for a total volume of 480 to 960 L. Pack securely for shipment in refrigerant packs. Store samples at 4 C upon receipt at the laboratory.

SAMPLE PREPARATION: 5. Remove samples from refrigerator and allow to equilibrate to ambient temperature. Prefilters may be analyzed for benzothiazole adsorbed on dust, or discarded. 6. If prefilters are to be analyzed, extract as follows: NIOSH Manual of Analytical Methods (NMAM), Fourth Edition