A 30-year-old man presented with eyelid dermatitis and was diagnosed with occupational allergic contact dermatitis to an epoxy resin based on the monomer diglycidyl ether of bisphenol F. He did not react to the standard epoxy resin based on bisphenol A, but reacted to a diluted sample of epoxy resin taken from his workplace, an adhesives manufacturing plant. The diagnosis would not have been made had he not brought samples from work, which were patch tested after appropriate dilution. The material safety data sheet provided additional evidence that the epoxy was not based on bisphenol A. The patient's symptoms subsided after avoidance of the identified product.