Can sulfuric acid ever be mixed with anything that would create a poisonous gas?
Poisonous gases can be created when sulfuric acid is mixed with either sodium hypochlorite (bleach) or sodium bisulfite. Mixing sulfuric acid and sodium hypochlorite together can produce hydrogen chloride gas. Hydrogen chloride gas is a strong oxidizer that is corrosive to all living tissue and can be fatal if inhaled. Combining sulfuric acid with sodium bisulfite can create sulfur dioxide gas. Sulfur dioxide gas is colorless and has an irritating, suffocating sulfurous odor. A third type of dangerous reaction produces hydrogen cyanide from the mixing of sodium cyanide and sulfuric acid. Hydrogen cyanide is highly toxic and can result in immediate death due to brief exposure. The National Fire Protection Association (NFPA) considers hydrogen chloride and sulfur dioxide to be third degree health hazards (serious temporary or residual injury). The NFPA has determined hydrogen cyanide to be a fourth degree health hazard (death or major residual injury). The NFPA also requires the labeling
