This SAE Recommended Practice establishes the instrumentation and procedure to be used in measuring the maximum exterior sound level for engine powered equipment under 20 rated bhp. It is intended to include equipment such as lawn mowers, snow blowers, tillers, etc. It is not intended to include equipment designed primarily for operation on highways or within factories and buildings, or vehicles such as motorcycles, snowmobiles, and pleasure motor boats that are covered by other SAE Standards or Recommended Practices. This SAE Recommended Practice may also be used when measuring the maximum exterior sound level on similar equipment powered by electricity or other power sources.