An irritant that causes tearing (watering of the eyes). "Real World" examples include onions, tear gas and pepper spray (capsaicin). Some typical lachrymating chemicals are thionyl chloride (SOCl2) and a crolein (CH2=CH-CHO). MSDS Relevance: Certain chemicals may say lachrymator on the label so treat these with respect. Use these only in a fume hood or with other local exhaust ventilation. Goggles or safety glasses are not adequate protection for lachrymators because the fumes and vapors can still reach your eyes directly or through inhalation. If you need personal protective equipment, a full-face atmosphere-supplying respirator is your best choice. The use of an eye wash can help flush a lachrymator out of your eye tissues and relieve some of the pain/irritation. Additional protectice measures such as gloves are also a good idea when working with lachrymators. Many of these are also skin irritants and/or corrosive. See also: Conjunctivitis, Eye Wash, Iridocyclitis, Irritant, Sternutator, Vesicant