On 17 April 1998, workers in the main turbine condenser bay detected a strong odor, described as that of propane or acetylene. Personnel were evacuated from the area, and the building ventilation system was used to purge the odor from the building. An ALERT Emergency Classification was declared as a precautionary measure as the licensee worked to identify and isolate the source of the odor. The source of the odor was later discovered to be an industrial lubricant from a gearbox being used in the main turbine condenser bay. This lubricant has a flash point of greater than 180 C (356F) and is not considered to be a fire hazard. Justification: This event is rated as out of scale in accordance with Part I-1.3 of the iNES Users Manual, as it did not involve any possible radiological hazard and did not affect the safety layers.