Page:NIOSH Manual of Analytical Methods - 6603.pdf/1
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| CARBON DIOXIDE | 6603 |
| CO₂ | MW: 44.01 | CAS: 124-38-9 | RTECS: FF6400000 |
| METHOD: 6603 | EVALUATION: FULL | Issue 1: 15 May 1989 |
| Issue 2: 15 August 1994 |
| OSHA: | 5000 ppm; STEL 30000 ppm | PROPERTIES: | gas; sublimes @ -78.5 °C |
| NIOSH: | 5000 ppm; STEL 30000 ppm | ||
| ACGIH: | 5000 ppm; STEL 30000 ppm (1ppm = 1.8 mg/m³ @ NTP) | ||
SYNONYMS: carbonic acid; dry ice
SAMPLING
| SAMPLER: | GAS SAMPLING BAG |
| FLOW RATE: | 0.02 to 0.1 L/min; fill bag ≤ 80% of capacity; spot samples (step 2.a.) or TWA samples (step 2.b.) |
| VOL-MIN: | |
| -MAX: | |
| SHIPMENT: | |
| SAMPLE STABILITY: | at least 7 days @ 25 °C [1] |
| BLANKS: | in a bag from a non-work area |
ACCURACY
| RANGE STUDIED: | 2270 - 10000 ppm [3] (3.5-L samples) |
| BIAS: | -2.5% [3] |
| OVERALL PRECISION (ŜrT): | 0.014 [1] |
| ACCURACY: | ±5.3% [1] |
MEASUREMENT
| TECHNIQUE: | GAS CHROMATOGRAPHY (PORTABLE), TCD |
| ANALYTE: | carbon dioxide |
| DESORPTION: | |
| INJECTION VOLUME: | |
| TEMPERATURE-INJECTION: | ambient |
| -DETECTOR: | 70 °C |
| -COLUMN: | ambient |
| CARRIER GAS: | He, 100 mL/min |
| COLUMN: | 1.5 m x 6-mm ID stainless steel, packed with 80/100 mesh Poropak QS |
| CALIBRATION: | bag standards or calibrated gas mixtures |
| RANGE: | 500 - 15000 ppm [2] |
| ESTIMATED LOD: | 1 ppm |
| PRECISION (S̄r): | 0.005 [1] |
APPLICABILITY: The working range is 500 to 15000 ppm (900 to 27000 mg/m³) in relatively non-complex atmospheres.
INTERFERENCES: Any compound having the same or nearly the same retention time as carbon dioxide on the column in use.
OTHER METHODS: This is method S249 in revised format [2].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94