HYD RO CAR BO NS, H ALO GE NAT ED: M ETH OD 1003, Issue 3, dated 1 5 Ma rch 2003 Page 2 o f 7 REAGENTS:
EQUIPMENT:
1. 2. 3. 4. 5.
1.
Ca rbon disulfide, chrom atog raph ic qua lity.* An alyte s, reagent grade quality. Nitrogen or helium, purified. Hydrogen, prepurified. Air, filtered.
See SPECIAL PRECAUTIONS.
2. 3. 4. 5. 6. 7.
Sampler: glass tube, 7 cm long, 6-mm OD, 4-mm ID, flame-sealed ends with plastic caps, containing two sections of 20/40 mesh activated (600 °C) coconut shell charcoal (front = 100 mg; back = 50 mg) separated by a 2-mm urethane foam plug. A silylated glass wool plug precedes the front section and a 3-mm urethane foam plug follows the back sec tion. Pre ssu re drop a cross th e tube at 1 L/m in airflow m ust be less than 3.4 k Pa. Tubes are comm ercially available (e.g., SKC
- 226-01 , Lot# 2000 or equ ivalent).
Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. Gas chromatograph, FID, integrator and colum ns (see pa ge1003 -1). Via ls, 2-m L, glass, P TFE -line d septum crim p caps. Volumetric flasks, 10-mL. Syringes, 10-µL to 1-mL, readable to 0.1 µL. Pipet, 1-mL, with pipet bulb.
SPECIAL PRECAUTIONS: Carbon disulfide is toxic and a serious fire and explosion hazard (flash point = !30 °C). W ork with it only in a hood. Several of the analytes are suspect carcinogens (Table 1). W ear appropriate protection clothing and work with these compounds in a well ventilated hoo d. SAMPLING: 1. Calibrate each personal sampling pump with a representative sampler in line. 2. Break the ends of the sampler imm ediately before sampling. Attach sampler to personal sampling pump with flexible tubing. 3. Sam ple at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size between the limits shown in Table 2. 4. Ca p the sam plers. Pac k secu rely for shipm ent.
SAMPLE PREPARATION: 5. Place the front and back sorbent sections of the sampler tube in separate vials. The glass wool plug should be included in the vial containing the front sorbent section. Discard the glass wool and foam plugs. 6. Add 1.0 mL CS 2 to each vial. C ap each vial. 7. Allow to stand 30 min with occasional agitation.
CALIBRATION AND QUALITY CONTRO L: 8. Ca librate daily with at leas t six wo rking standa rds over the appro priate rang e from below the LOD to 10x the LO Q or grea ter if required (see T able 3). a. Add known amounts of neat analyte or calibration stock solution to CS 2 in 10-mL volumetric flasks and dilute to the mark. b. Analyze with samp les and blanks (steps 11 and 12). c. Prepare calibra tion gra ph (p eak area vs. :g analyte).
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition
