What is the standard for in-car noise at 120 km/h?
2 Answers
If a car reaches a speed of 120 km/h, the in-car noise should be below 69 decibels to meet the standard. Introduction to the sources of car noise: When a car is in operation, it generates noise, causing noise pollution both inside and outside the vehicle. Generally, in-car noise primarily comes from engine noise, road noise, tire noise, wind noise, resonance noise, and other sources. Introduction to car noise standards: Typically, car noise should be below 60 decibels. According to the technical requirements for the safe operation of motor vehicles, the noise level inside passenger vehicles should not exceed 82 decibels, and the noise level near the driver's ear should not exceed 90 decibels. In-car noise below 60 decibels is considered acceptable, while 40 to 60 decibels is equivalent to normal conversation levels.
Driving at 120 km/h, cabin noise is quite crucial. Having researched cars for years, I feel there's no global unified standard, but the industry typically references norms like ISO 5128. Generally, sedan noise levels range between 60 to 70 decibels, equivalent to normal conversation. SUVs and pickups are slightly higher, possibly over 70 decibels, dominated by wind and tire noise. Testing requires professional equipment on straight roads at constant speeds. Many factors influence this—new cars with good sound insulation may drop to 50 decibels, while older cars or those with severely worn tires can rise to 80 decibels. It's advisable to regularly check door seals and switch to quiet tires, as excessive noise can be exhausting. Actual differences vary widely; using a mobile app during test drives gives more reliable measurements. Don’t rely solely on brand claims—personal experience determines comfort.
