This study was conducted to evaluate the charcoal tube sampling method for carbon disulfide in the air. Breakthrough was investigated according to flow rate, sampling time and air volume. Also the storage stability by storage method and time was investigated. The results are summarized as follows.
1. The samples stored at room temperature (28.2℃), refrigerator (3.8℃) and freezer (-15.6℃) were analyzed every week to five weeks. At one week storage at room temperature, 3.5% of CS₂ in the front section of the charcoal tube migrated into the back section and 57.7% at five weeks. The amount of CS₂ in the back section of the charcoal increased continuously by storage time. Migration of CS₂ was slow at refrigerator, and stopped occur at freezer. Recovery rate CS₂ was 52-82% at room temperature and 92-101% at refrigerator, based on the amount at freezer as a reference value. Thus loss was observed at room temperature.
2. When 6-48 L of fresh air were passed through tubes with spiked amounts of 0.379 and 0.759㎎ sample, the amounts of CS₂ is the back section of charcoal were 5.7-132.4 and 0-92% of the amount in the front section, respectively. The total recovery rates of CS₂ from 0.379 and 0.759㎎ spiked sample were 35.7-101.0% and 91.3-100.1%, respectively. CS₂ loss was observed in 0.379㎎ spiked sample, but not in 0.759㎎ spiked sample. In the spiked samples, the amount of CS₂ in the back section of charcoal was not affected by flow rate when the air volume was controlled. The amount of CS₂ in the back section of charcoal increased over sampling time. And the faster the flow rate, the more the migration amount when the sampling time was the same.
3. A known concentration, 10 ppm of CS₂, was produced in a 200 L Tedlar bag. When the air volume was 24, 36, 48 L, breakthrough was 5.8, 16.9, 47.4%, respectively. The sampling flow rate of 0.05, 0.1, 0.2 Lpm did not change the breakthrough rate. Breakthrough increased over sampling time. And the faster the flow rate, the more the breakthrough, when the sampling time was the same.
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