The dayâeveningânight noise level or Lden is a 2002 European standard to express noise level over an entire day. It imposes a penalty on sound levels during evening and night [1] and it is primarily used for noise assessments of airports, busy main roads, main railway lines and in cities over 100,000 residents. [2] [3] [4] The penalty for sound production during evenings and nights is due to higher nuisance perception during quieter hours and to prevent sleep deprivation for nearby residents.
Lden is calculated as: [5]
Where the long-term average noise levels are defined as:
Part of the day | hours | penalty (dB) |
---|---|---|
day | 07:00 - 19:00 | 0 |
evening | 19:00 - 23:00 | 5 |
night | 23:00 - 07:00 | 10 |
The exact hours of the three periods may be chosen differently by individual EU member states.
The formula for Lden can be considered a weighted average of the yearly individual noise level during day, evening and night.
The dayâeveningânight noise level or Lden is a 2002 European standard to express noise level over an entire day. It imposes a penalty on sound levels during evening and night [1] and it is primarily used for noise assessments of airports, busy main roads, main railway lines and in cities over 100,000 residents. [2] [3] [4] The penalty for sound production during evenings and nights is due to higher nuisance perception during quieter hours and to prevent sleep deprivation for nearby residents.
Lden is calculated as: [5]
Where the long-term average noise levels are defined as:
Part of the day | hours | penalty (dB) |
---|---|---|
day | 07:00 - 19:00 | 0 |
evening | 19:00 - 23:00 | 5 |
night | 23:00 - 07:00 | 10 |
The exact hours of the three periods may be chosen differently by individual EU member states.
The formula for Lden can be considered a weighted average of the yearly individual noise level during day, evening and night.