Tedlar Bag
| Tedlar bags are manufactured from PVF (Tedlar) film. They are generally considered inert and can be used to collect samples containing common solvents, hydrocarbons, chlorinated solvents, and many other classes of compounds. They are commonly used to collect low-level sulfur gases, but only if the bag fittings are non-metallic (polypropylene, Teflon, or Nylon). Sample hold time will vary for different classes of compounds:
The surface of a Tedlar bag is a work in progress. The surface of a new bag is essentially free of VOCs at the single digit ppbv level. Once used, however, the surface has been exposed to moisture and possibly organic compounds. It may irreversibly adsorb many VOCs at the low ppbv level. A series of purges with high purity gas will not remove VOCs from the surface. |
24 hours