Noise ratings cover the three areas of conservation of hearing, speech communications, and annoyance. Correction for the intermittent noise exposure from a chain saw can be computed (based on a day-by-day log of a chain saw operation in the woods). Temporary threshold shift a measure of permanent threshold shift or hearing loss.
Noise considerations and factors are: noise measurement, including approximate meterless methods; muffler design; and noise sources other than exhaust.
Vibration in 2-stroke cycle internal combustion engines, and distribution of vibration amplitude over a chain saw operator's arm are discussed. Physical injury is shown to be a function of the amplitude/frequency ratio. Disagreeable vibrations and injurious vibrations are not necessarily the same.