Thanks PuddingBowl.

The TGA is the Therapeutic Goods Administration and here in Australia, rumour has it that they don't want us "engineering" things outside of their intended use...hence Bubble PEP. I don't know if there has been any specific directive as yet.

Threshold PEP is about $18 per unit and is available from Respironics. I know PariPEP allows for a mnaometer to be attached to measure accurate amount of PEP. Was just wondering if anyone else has had any experience with them.

Does the reference your are talking about in Pryor state where they get the figure 10-20cmH20? Just wondering where this magic number has come from.

Thanks