The chain saw designer tries to protect the logger from three main hazards: cuts and bruises, vibration injury, and hearing impairment. Each of these problems is examined in terms of severity and solution. The availability of field data, as they affect the writing of safety standards and regulations, are also examined.Progress is being made. Chain brakes and special chains have been introduced in an attempt to solve the kickback problem. A number of units meet most existing European vibration standards. Noise levels are still higher than desirable on most models, but muffler development is beginning to reduce exhaust noise toward mechanical noise levels.