Well I learned something today. However, your link only half-supports what you seem to be claiming.
Here's something more succinct.
http://www.mayoclinic.org/healthy-living/adult-health/expert-answers/third-hand-smoke/faq-20057791
Right at the top, If smoking is done outdoors, as is the case in practically every business, then what? The residue is left on clothing, but that gets washed regularly which ought to limit how much the residue can build up. We don't even know the full risks of third-hand smoke in buildings, so there's no way to quantify the measurable danger, if any, posed by the smoker themself.
Bottom line: third-hand smoke in buildings is recognized and serious, but fourth-hand smoke on smokers themselves is not recognized and unlikely to be serious. Furthermore, there is a quickly growing segment of smokers who won't touch a cigarette, and little to none of the above applies to them at all.