Yeah, no doubt. Probably the only way to get anything remotely similar on board would be to lie and claim that you are using an oxygen concentrator for health reasons (since they have a filter) and add an activated-charcoal filter and mask. That should neutralize the fumes and the pathogen-bearing particulates that children and inconsiderate adults launch into the atmosphere when they don't cover their mouths when sneezing or coughing. Sure, the goons might shoot you down, but then they might not. Also might be useful in theaters or other enclosed spaces with hundreds of other oxygen breathers or noxious floating aromatic hydrocarbons.
Speaking of that last thing. Someone told me that forests are unhealthy to stay in for long because the pine trees emit aromatic hydrocarbons (turpene) which are potentially carcinogenic and harmful to the lungs. I know that turpentine is made from pine sap, but I wonder if it's toxic to breathe the fumes from pine trees. If so, the next time I go hiking or back-packing I might just take along one of the units in this thread - since I can't take it with me on airplanes...
