eTable 1. Noise metrics and their definitions*1.
| Abbreviation | Definition |
| dB | Logarithmic scale for sound pressure levels |
| Leq | Average value of an energy-equivalent continuous sound level over a period of time |
| LAeq | A-weighted Leq |
| LDay | LAeq for daytime hours (usually 7:00 am – 7:00 pm)*2 for all day periods of a year |
| LEvening | LAeq for evening hours (usually 7:00 pm – 11:00 pm)*2 for all evening hours of a year |
| LNight | LAeq for nighttime hours (usually 11:00 pm – 7:00 am)*2 for all nighttime hours of a year |
| LDN | All 24 h LAeq periods of a year with additional 10 dB for nighttime noise annoyance (usually from 11:00 pm –7:00 am)*2 |
| LDEN | All 24 h LAeq periods of a year with additional 5 dB for evening hours (8:00 pm – 10:00 pm or 7:00 pm – 11:00 pm)*2 and additional 10 dB for nighttime hours (10:00 pm – 6:00 am or from 11:00 pm – 7:00 am)*2 |
| NAT6 | Maximum level which is exceeded six times above 50 dB without upper limit during the night (from 10:00 pm – 6:00 am). At the same time, the 24 h continuous sound level is below 40 dB. |
*1 adapted according to directive 2002/49/EC
(European Parliament and European Council, 2002)
*2 In Germany, normal sleeping hours are defined in the respective federal states immission control legislation and usually encompasses the period from 10:00 pm – 6:00 am. Therefore, German studies (e.g. NORAH study) sometimes deviate from the periods for L Day /L Evening /L Night listed in eTable 1 and instead use the periods stipulated in the legislation.