• The association between exposure to UV radiation and corneal disease was investigated in 838 watermen who work on the Chesapeake Bay, Maryland. Individual ocular exposure was calculated by combining a detailed occupational history with laboratory and field measurements. Pterygium was found in 140, climatic droplet keratopathy in 162, and pinguecula in 642. Logistic regression analysis showed that pterygium and climatic droplet keratopathy were significantly associated with a broad band of UV radiation exposure (UV-B, 290 to 320 nm; A1, 320 to 340 nm; and A2, 340 to 400 nm), but the association with pinguecula was weaker. Simple measures such as wearing a hat or spectacles protect the eye and could potentially reduce the amount of pterygium and climatic droplet keratopathy attributable to UV radiation exposure.