For measuring the air concentration of chemicals including formaldehyde.
These tubes are used to measure the average concentration of potentially harmful vapors in the air over a defined sample period. To use, the tube is connected to a small vacuum pump that draws air through the tube at a precise flow rate over a period of time. After the sample is taken, the tube is transported to a laboratory where they can remove the adsorbent material and perform analysis by solvent extraction and gas chromatography (GC) to determine the quantity of chemical collected, from which a time-weighted average (TWA) concentration can be calculated.
| Sorbent Material
|| Silica Gel treated with DNPH (2,4-Dinitrophenyl hydrazine)
| Flow Resistance
|| ≤ 10 kPa at flows up to 500cc/min
| Operating Temperature Range
|| 10 to 40o C between 20-80% RH
| Blank Tube Background
|| ≤ NIOSH LOD for the target vapor
| Standards Compliance
|| ISO 22065
||Primary Sorbent Weight
||Backup Sorbent Weight
|ZST-055 / ZST-055A
- Not recommended for collection of Acrolein.
- Ozone may cause interference.
- Tubes may off gas small amounts of Acetonitrile. Do not sample for Acetonitrile at the same time as using these tubes.
Additional Information Available
Zefon Silica Gel DNPH Sorbent Tube Operating Instructions