Iron Out and CLR mixed - toxic gas?
Most likely, sulfur dioxide. $\ce{SO2}$. was produced. The ingredients sodium hydrosulfite, $\ce{Na2S2O4}$, and sodium metabisulfite, $\ce{Na2S2O5}$, when mixed with acid, release $\ce{SO2}$, which oxidizes to $\ce{SO3}$ eventually.

$\ce{SO2}$ is quite irritating, but not immediately damaging in low doses, &lt;100 ppm, though it can certainly induce a life-threatening asthma attack. "Sulfur dioxide is mildly toxic and can be hazardous in high concentrations. Long-term exposure to low concentrations is also problematic." $\ce{SO3}$ is even more dangerous, since it forms sulfuric acid when it meets water, e.g. in tears in the eye.

Air the room *thoroughly. There is not much else to do: theoretically, ammonia could be used to form a salt, removing the gas from air, but there is no way you could balance the reaction, leaving you with an excess of one irritant or another.