What is the decibel level of car noise?
2 Answers
Car interior noise is below 60 decibels, which falls within the range of normal conversation sounds (40-60 dB). According to GB14952002 regulations, the external noise limit for passenger cars (M1 category vehicles) is 74 dB. Currently, there are no mandatory standards for interior noise levels in passenger cars. The vehicle engine is one source of noise, with noise levels varying according to engine RPM (primarily generated and transmitted through: front fenders, hood, firewall, and exhaust pipe). Road noise occurs during high-speed driving due to wind resistance and chassis vibrations caused by movement, as well as from gravel impacting the vehicle's underbody. These constitute the main sources of road noise (primarily generated and transmitted through: four doors, trunk, front fenders, and front wheel arches).
The decibel level of car noise varies greatly due to multiple factors. When driving in the city at idle or low speeds, the noise is typically around 50 to 60 decibels, equivalent to a normal conversation level, which is quite comfortable. However, once on the highway at higher speeds, the noise can surge to 70 to 80 decibels or more, like having a hairdryer next to your ear. This is mainly influenced by speed—wind resistance and tire friction noise increase at higher speeds. From my own experience, driving an SUV tends to be noisier due to the higher chassis, which is more prone to wind noise. Additionally, the engine type plays a key role: electric vehicles usually stay around 60 decibels, much quieter; combustion engine cars can add about 10 decibels with engine roar. Regular maintenance, such as changing tires and checking the hood, can help reduce noise and make driving more pleasant.
