How Many Decibels is a Car Horn?
3 Answers
Regarding the standard "Performance Requirements and Test Methods for Horns Used in Motor Vehicles": The horn should be installed at the front of the motor vehicle. For light motorcycles with a power below 7kW, the noise must be between 95-115 decibels, while for four-wheeled motor vehicles and motorcycles with a power above 7kW, the noise must be between 105-118 decibels. Below is relevant information: 1. Definition of a horn: A horn is an audio signaling device in a car. During driving, the driver uses it as needed and according to regulations to emit necessary sound signals, warning pedestrians and alerting other vehicles to ensure traffic safety. It is also used for urging movement and conveying signals. 2. Correct methods for using a horn: (1) At intersections without signals or supervision, it is recommended to use the horn for alerting, with a maximum of three honks; (2) On mountain roads, curves, and blind spots (intersections without auxiliary mirrors), it is recommended to use the horn for alerting, with a maximum of three honks; (3) When overtaking on highways, use the horn in conjunction with lights to alert vehicles in adjacent lanes; (4) When alerting problematic vehicles on the road, it is recommended to first use lights for signaling. If ineffective, then use the horn for alerting, preferably informing the other vehicle while in a stopped state.
I've been driving for over twenty years, mostly in the city. The loudness of car horns typically ranges between 90 to 110 decibels. I've tested it several times myself, and there's a noticeable difference between old and new cars – older cars might only reach around 90 decibels, sounding muffled, while newer ones often exceed 105 decibels, with a strong penetrating power that effectively alerts pedestrians at intersections. Decibels measure sound intensity, and 110 decibels is equivalent to the noise from a construction site pile driver. The high volume is designed to ensure safety in noisy environments, such as during heavy fog or in blind spots, where honking can be life-saving. However, excessive loudness isn't ideal either. I've seen some drivers honking aggressively in residential areas, which can harm the hearing of those nearby. I recommend using the horn lightly and only when necessary while driving, and don't delay maintenance to avoid failure in critical moments. Additionally, weather and environmental conditions can affect the actual sound effect, like rain possibly dampening the volume a bit.
Decibels are the unit used to measure sound intensity. I've measured car horns typically ranging between 90 to 110 decibels - my family sedan's horn registers just over 100 dB. That's loud enough to match the noise of standing at a subway entrance during train arrival. Why this range? Primarily to ensure audibility by other drivers and pedestrians during highway driving or congested traffic, preventing collision risks. However, I believe excessive volume contributes to urban noise pollution and neighborhood disturbances. I always decelerate first and tap the horn lightly to minimize public nuisance. Additionally, decibel levels vary by brand - imported vehicles may feature more moderate designs, though all comply with regulatory limits (typically capped at 115 dB in most regions). Maintenance checks should include wiring inspections - blown fuses can reduce volume, compromising safety.
