Vomit is a more dangerous material to inhale than, say, pond water. As little as a quarter of a mouthful can cause significant damage. The stomach acid that is a routine ingredient in vomit will handily digest the lining of the lungs. Also, vomit, unlike (hopefully) pond water, often includes chunks of recently ingested food: things to get stuck in your windpipe and suffocate you. If stomach acid can digest a lung, imagine getting it in your eyes. “Barf bouncing off the helmet and back into the eyes would be really debilitating,”
