Which statement about TIH examples commonly encountered is accurate?

• A. Phosgene and hydrogen sulfide are commonly encountered TIHs
• B. Only chlorine qualifies as TIH
• C. TIH is a term for all solids
• D. TIH hazards are never toxic

Answer: (A)

TIH means Toxic Inhalation Hazard—the dangerous substances are those whose primary risk comes from inhalation, typically gases or highly volatile liquids that can affect breathing and physiology quickly.

Phosgene and hydrogen sulfide are classic TIHs that responders commonly encounter. They’re both highly toxic and pose serious inhalation risks, with rapid onset and serious potential health effects, which is why they’re often highlighted in training. The idea that only chlorine qualifies as a TIH isn’t correct because many other substances fit the TIH category, including phosgene and hydrogen sulfide. TIH isn’t limited to solids, and to say TIH hazards are never toxic is false—the whole point of TIH is their toxicity by inhalation.