National Marker Company signage with legend “DANGER – NO SMOKING OXYGEN IN USE” is often used to prohibit people from smoking around the areas equipped with combustible oxygen. Commonly used at commercial and industrial locations, warehouses, workplaces and jobsites, this sign is often used as a part of safety measures too where smoking can lead to fire-related safety hazards. Jobsites that handle possibly inflammable solvents, or materials are usually very specific about putting-up such danger signage across the premises. This OSHA signage is easy to spot and read, ensuring working personnel and visitors are immediately prohibited from smoking-related restrictions.