15. One of the most poisonous gases that has a rotten egg'odor. Ammonia d. Hydrogen sulphide b. Nitrogen dioxide e. Sulfur dioxide Methane a. c. a. 16. What factor does not affect toxicity of a harmful agent in humans? Medical condition d. Duration of exposure b. Individual susceptibility e. Individual susceptibility c. Fundamental substance toxicity f. None of the above 17. Gas that does not have physiological effect on person and is dangerous only if it displaces oxygen. a. Carbon dioxide d. Ammonia b. Carbon monoxide e. Nitrogen C. Methane f. Nitrogen dioxide