Noise contours are lines on a map that represent equal noise levels. These contours form a series of closed curves, with each curve enclosing areas exposed to the same levels of aircraft noise. As expected, noise levels tend to be higher closer to the source and lower further away. This is particularly true at airports, where aircraft generate more noise when closer to the ground, while noise decreases as they ascend and move further from the runways. 

Noise Contour Uses 

Noise contours are a key tool in assessing the impact of aviation noise on surrounding communities. They allow comparisons of noise exposures in different areas around an airport and between airports.  

Many noise mitigation measures, such as noise insulation programmes, are based on noise contours to define a fair and consistent eligibility threshold. 

Calculating Noise Contours 

Noise contours are calculated using computer models that take into account all aircraft activity at an airport, including details such as: 

• Runway locations 
• Aircraft movements (type of aircraft, number of flights, time of day) 
• Arrival and departure routes, as well as destinations (to account for fuel load) 
• Distribution of aircraft movements across runways and flight paths
• Data from Noise Monitoring Terminals