Urethane paints usually do smell until fully dry. Make sure you ventilate your work area and DO wear a proper respirator. Urethane paints and clears are potentially dangerous as they contain methyl isocyanate, which, according the the EPA, methyl isocyanate is extremely toxic to humans from acute (short-term) exposure. In Bhopal, India, accidental acute inhalation exposure to methyl isocyanate resulted in the deaths of about 3,800 people and adverse health effects in greater than 170,000 survivors. Pulmonary edema was the probable cause of death in most cases, with many deaths resulting from secondary respiratory infections. Survivors continue to exhibit damage to the lungs and eyes. Reproductive effects and increased number of stillbirths and spontaneous abortions were noted in the survivors of the Bhopal, India accident. EPA has classified methyl isocyanate as a Group D, not classifiable as to human carcinogenicity. Just saying...