Generator noise levels vary greatly from model to model, with decibel ratings that range from 51.5 dB for a Yamaha EF2000iS inverter generator to 72 dB for a DuroMax Elite portable generator. Inverter generators usually produce less noise than other generators.
Typical portable generators produce noise levels ranging from around 70 dB up to 85 dB, while inverter generators produce lower noise levels ranging from about 50 dB up to about 65 dB. For a larger, whole-house backup system, a Kohler Power Systems 20 kW residential standby generator emits 69 db of noise. Because decibels are measured on a logarithmic scale, a decibel rating that is 10 points higher is twice as loud. For example, a typical vacuum cleaner operates at about 70 dB while an average conversation is about 60 dB.
Generator noise levels vary based on their capacity and on what percentage of their capacity they are producing. Even the very quiet Yamaha EF2000iS inverter generator is twice as loud when running at full load as it is when running at 25 percent capacity. The Kohler 20 kW standby generator is twice as loud as the Yamaha EF2000iS, but it produces 10 times as much power. Both inverter generators and standby generators are designed for low noise output and intended to be used in areas near other people.