Scentroid is the only manufacturer offering PTFE air sampling bags. These bags offer a much higher resistance to contamination and Scentroid PTFE Sample Bag have a longer holding time than Tedlar bags. They are also accepted bag material for all standards. PTFE Sampling bags are extremely resistant to contamination and therefore can be easily cleaned and reused. PTFE sample bags are already approved by the Ministry of Environment in Ontario and almost every other jurisdiction around the world.