Check online for a few resources for masks, etc.
The typical treatments for chemical and/or bio attack would be to evacuate the area. THAT would be a legitimate "bug-out" scenario IMO.
I don't know that there is a magic bullet for any and all scenarios. How often do you see areas needing to be evacuated because a train derailed and dumped chemicals somewhere? You really can't "protect" against stuff like that, you have to leave the area. Grab a gun, the dogs, and the wife, and drive out of town for a mini-vacation.
Not sure about creating your own lab, may not be doable.