How long does marijuana stay in your system of you smoked it once? Someone who smokes occasionally-or for the first time-will  likely test positive for 1-3 days afterward, according to a review  by the  National Drug Court Institute (â¦ NDCI).ow long does marijuana stay in your system of you smoked it once? Someone who smokes occasionally-or for the first time-will  likely test positive for 1-3 days afterward, according to a review  by the  National Drug Court Institute (â¦ NDCI).
Chemical hazard. A chemical hazard is a type of occupational hazard caused by exposure to chemicals in the workplace. Exposure to chemicals in the workplace can cause acute or long-term detrimental health effects.
Chemical safety is the application of the best practices for handling chemicals and chemistry processes to minimize risk, whether to a person, facility, or community. It involves understanding the physical, chemical, and toxicological hazards of chemicals. Chemical health is a subset of chemical safety that focuses on toxicology and health risks. Chemical hygiene is essentially the same as chemical safety. It is the collection of best practices used to minimize chemical exposure, whether to workers or the community.