Enter the speed of the vehicles and the distance from the road into the calculator to estimate the road noise level in decibels (dB).
Road Noise Formula
The following formula is used to estimate the road noise level:
NL = 70 + 10 * log10(S) - 20 * log10(D)
Variables:
- NL is the noise level (dB)
- S is the speed of the vehicles (mph)
- D is the distance from the road (feet)
To estimate the road noise level, use the formula where 70 represents a base noise level in dB at a reference speed and distance, 10 * log10(S) accounts for the increase in noise with speed, and -20 * log10(D) accounts for the decrease in noise with distance from the road.
What is Road Noise?
Road noise is the sound generated by vehicles traveling on roadways. It is a type of environmental noise that can be disruptive to nearby residents and wildlife. Factors that contribute to road noise include vehicle speed, traffic volume, road surface, tire design, and the distance from the road. Understanding and calculating road noise levels can help in the design of noise barriers and other mitigation strategies.
How to Calculate Road Noise?
The following steps outline how to estimate the Road Noise Level.
- First, determine the speed of the vehicles (S) in miles per hour (mph).
- Next, determine the distance from the road (D) in feet.
- Next, gather the formula from above = NL = 70 + 10 * log10(S) – 20 * log10(D).
- Finally, calculate the Road Noise Level (NL) in decibels (dB).
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem:
Use the following variables as an example problem to test your knowledge.
Speed of the vehicles (S) = 55 mph
Distance from the road (D) = 100 feet
