Question 2874 Deck General

The correct answer is D) the sense of smell is deadened by the gas. Hydrogen sulfide (H2S) gas can deaden a person's sense of smell, making it unreliable as a detector. The gas acts as a nerve toxin, paralyzing the olfactory nerve and preventing the detection of its characteristic rotten egg odor. This can lead to a false sense of security, as a person may no longer be able to smell the gas even as it reaches dangerous concentrations. The other options are incorrect, as H2S is not odorless, and eye irritation is not a reliable indicator compared to the loss of smell. Relying on the sense of smell alone is not recommended for detecting H2S, which can quickly become undetectable to the individual exposed to it.