conveyors range from 113 dBA to 119 dBA per 100 m for typical 10,000 TPH 5 m/s coal conveyors. This paper presents results for standard and alternative idler roll designs, referred to as "low noise" and "super low noise" conveyors. Such conveyors produce sound power levels of 107 dBA and 101 dBA per 100 m respectively, while