Noise Pollution Calculator — Formula
## How to Calculate Noise Pollution
Noise levels are measured in decibels (dB) on a logarithmic scale.
### Combining Sources
**Combined dB = 10 * log10(10^(dB1/10) + 10^(dB2/10))**
### Distance Attenuation
**dB at distance = Source dB - 20 * log10(distance / reference)**
### Reference Levels
- Whisper: 30 dB
- Conversation: 60 dB
- Traffic: 70-85 dB
- Construction: 80-100 dB
- WHO recommends daytime limit of 55-65 dB
Noise levels are measured in decibels (dB) on a logarithmic scale.
### Combining Sources
**Combined dB = 10 * log10(10^(dB1/10) + 10^(dB2/10))**
### Distance Attenuation
**dB at distance = Source dB - 20 * log10(distance / reference)**
### Reference Levels
- Whisper: 30 dB
- Conversation: 60 dB
- Traffic: 70-85 dB
- Construction: 80-100 dB
- WHO recommends daytime limit of 55-65 dB
Exemplo Resolvido
A 70 dB traffic noise and 60 dB HVAC system, 8 hours exposure at 50 feet.
- Combined: 10 * log10(10^7 + 10^6) = 10 * log10(11,000,000) = 70.4 dB
- At 50 ft: 70.4 - 20 * log10(50/3) = 70.4 - 24.4 = 46.0 dB
- vs WHO: 46.0 - 65 = -19.0 dB (below limit)