Ask a Radon Specialist, however, I do not believe the cigarette smoke will trigger a poor Radon reading. Smoking in a home is stinky enough but it shouldn't trigger a false reading. Radon is a naturally occurring "invisible" and "odorless" gas produced buy decaying matter in the earth. Some areas have stronger "prongs" of Radon, like Pennsylvania, areas of New Jersey, (Called The Reading Prong), some areas of NY. Check with your local Radon specialists regarding your concerns.