Although more and more states are adopting smoking restrictions in workplaces, restaurants, and bars to protect people from the dangers of second-hand cigarette smoke, health care workers continue to be exposed to similar dangers every day in the form of surgical smoke. During surgical procedures that use a laser or electrosurgical unit, the thermal destruction of tissue creates a smoke byproduct. According to the NIOSH research studies have confirmed that this smoke plume can contain toxic gases and vapors such as benzene, hydrogen cyanide, and formaldehyde; bioaerosols; dead and live cellular material (including blood fragments); and viruses.