A 25-year-old man developed severe shortness of breath, constricting chest pressure, chest pain, cough and myalgia following acute exposure to a waterproofing aerosol that contained trichloroethane. He became febrile and developed a small area of atetectasis with significant hypoxemia. Recovery was complete within 36 hours. This experience suggests that casual use of a trichloroethane aerosol with a surface active agent can cause acute pulmonary toxicity. The mechanism of this injury is unknown.