The noise from aircraft landing and taking off is calculated according to the method established by Italian law for this sector (DM 31/10/97) using, as an indicator, the so-called LVA index (Livello di Valutazione del Rumore Aeroportuale - Airport Noise Level Assessment).
The noise monitoring terminals are located in various positions in the area around the airport on the paths of aircraft movement. Each terminal records the noise generated by the aircraft flying overhead, quantified by various parameters including the SEL (Sound Exposure Level). The logarithmic sum of all SEL recorded by each terminal in a given day determines the daily LVA for that terminal. The daily LVA and monthly LVA average for each terminal are published and available for public consultation.
The annual LVA is the logarithmic average of the daily LVA data recorded in the peak three week period; these are the weeks with the largest number of movements, identified as the following three quarters of the year: 1 January - 31 January and 1 October - 31 December, 1 February - 31 May, 1 June - 30 September.
ARPA - Bologna Provincial Section periodically checks the LVA data recorded by the airport noise monitoring system.
Monitoring terminals have been placed in positions which correspond to Bologna Airport’s approach routes and take off routes.
Observing the image, you can see how the units have been placed so that they can follow the route of the aircraft and record noise produced by all the flights to and from Bologna Airport. The terminals nearest to the Airport (1,3,6) will therefore record the highest levels of noise. Number 6 has been chosen from these units as the LVA (Italian Airport Noise Level) reference terminal.
| NMT n. | Location |
|---|---|
| 1 | Via del Bargellino (Calderara di Reno) |
| 3 | Aeroporto |
| 4 | Via Crocetta (Calderara di Reno) |
| 5 | Via Zanardi 393 |
| 6 | Centro Sportivo "Pizzoli" |
| 7 | Museo del Patrimonio Industriale |
| 8 | Giardini Casa buia Arcoveggio |
| 9 | Ippodromo Arcoveggio |
Image in high definition (pdf format - 3Mb).
LVA (Italian Airport Noise Level) is calculated, in accordance with the law (v. D.M. 31/10/1997 All. A), as follows:
- Monitoring terminals record noise from aircraft using SEL as a parameter (Sound Exposure Level).
- The year in question is divided into three 4-month periods:
- 1 October – 31 January.
- 1 February – 31 May.
- 1 June – 30 September.
- Days are divided into two periods:
- Day (06.00-23.00).
- Night (23.00-06.00).
- Daily LVA is calculated (day LVA + night LVA):
- Day LVA is the sum total of all data for SEL recorded during the day period.
- Night LVA is the sum total of all data for SEL recorded during the night period (10 dB is added to all night SEL data due to the fact that noise from aircraft is more audible at night).
- Weekly LVA is calculated as the logarithm average of relevant day LVA.
- The three test weeks for air traffic are then identified based on the three periods in point 2 above.
- The logarithm average of the three relative values for weekly LVA gives us the legal LVA.
- The legal LVA must not be above 65 dB (A) for residential areas.