Sound power ranking of three circular saws with 12 saw blades, and of a blade stiffener while considering feed rate and feed force

Permanent hearing loss and tinnitus are common among construction workers. Saws are thought to be a significant contributor to worker noise over-exposure in the woodworking industry. Many saw blades claim to have low noise and vibration; the literature claims that noise reductions of 5 to 10 dB are commonplace. To better understand the currently available noise reduction options for saw blades, sound power measurements were made in the loaded and unloaded conditions for three circular saws with 12 saw blades with and without a blade stiffener. In the loaded condition, the material cut was one-inch thick rough-cut oak. Oak was used as a hardwood. During sawing, the feed force and feed rate were measured. The sound power (watts) was divided by the feed rate (inches/second) to calculate the average sound power per unit of material cut. This feed-rate-adjusted sound power level was used to compare the performance of blades and saws. It was found that the difference in feed rate adjusted sound power level between the highest and lowest saw setups was approximately 10 dBA. The saw and blade combination with the lowest feed rate adjusted sound power used a DC motor, a thin kerf blade, and a blade stiffener.