Noise exposure levels from model airplane engines

Previous research indicates that noise levels from unmuffled model airplane engines produce sufficient noise to cause TTS. The present study explored SPLs of smaller engines under 3.25 cc (.19 cu. in.) and the effectiveness of engine mufflers. Results showed that model airplanes can exceed a widely used damage risk criterion (DRC) but that engine mufflers can reduce levels below DRC. Handling model gasoline engines should be added to the list of recreational activities such as snow-mobile and motorcycle riding, shooting, etc. in which the participant's hearing may be in jeopardy. Suggestions are presented to the model engine enthusiast for avoiding damage to hearing.