Factories and other work locations have long utilized large, “active” sensing stations to maintain safe conditions for their employees. Typically, these were situations in which large quantities of chemicals were handled directly and the need for continuous monitoring was obvious. More recently, awareness of the exposure to various chemical compounds in routine, daily life has grown. Outgassing from plastics, furniture and carpeting, leaching of plasticizers from innumerable sources, the widespread use and disposal of various medicines, as well as other formerly ignored sources of exposure are now a source of concern in a diverse array of workplace situations and in the home.