Title of Example

Example

Introduction

The city of Venice urban air quality network is working, with the present structure, since 1999, when the two air quality networks (the Municipality’s one and the Province’s one) settled in the urban territory have been unified under the technical management of the Regional Agency for Protection of the Environment (ARPAV, Provincial Department of Venice).

Nine monitoring stations are placed in the urban area of Mestre and Marghera, that is the mainland part of the Municipality, while only one station is located in the historical centre of Venice, for a total of eleven stationary stations to monitor Venice’s air quality. Two mobile laboratories are also available to cover short-period monitoring campaigns too.

Monitoring stations are classified following the National Decree 20/05/1991 (Ministry of Environment), that distinguishes between: urban background stations (type ‘A’); urban residential areas stations (type ‘B’); stations exposed to road traffic (type ‘C’); extra-urban stations, to study photochemical pollutants (type ‘D’).

At the moment, stations have been re-classified and there are some proposals for the urban air quality network optimisation: both actions derive from Air Quality Framework Directive (and Daughter Directives) guidelines, the EUROAIRNET criteria (according to an initiative of the Veneto Region Authority), and the Decision of the Council on the Exchange of Information.

Figure 1 - City of Venice: existing air quality monitoring stations

In Figure 1 it is possible to see:

- 6 urban background monitoring stations: Parco Bissuola station, located in a green area of Mestre and via Bottenigo station, located in a Marghera area not directly influenced by relevant emission sources (both were previously classified as type ‘A’ stations); Sacca Fisola, viale San Marco and via A. Da Mestre are located in urban densely populated sites (they were previously classified as type ‘B’ stations); Maerne is needed for photochemical pollution and secondary pollutants monitoring (it was previously classified as type ‘D’ station);

- 3 urban traffic monitoring stations: Corso del Popolo, via Circonvallazione; and via Fratelli Bandiera are stations for car traffic pollution monitoring (they were previously classified as type ‘C’ stations);

- 1 suburban industrial monitoring station: Malcontenta is located in the area influenced by Porto Marghera industrial emissions (it was previously classified as type ‘B’ station).

SO₂ Monitoring

Seven monitoring stations are provided with automatic analyzers of Sulphur Dioxide (SO₂): Parco Bissuola; via Bottenigo; Sacca Fisola; viale S. Marco; via Antonio Da Mestre; Maerne; Malcontenta.

Instruments used for SO₂ monitoring are located inside the monitoring stations and are based on the Ultraviolet Fluorescence method (in compliance with the reference method of EU Directives ISO/DIS 10498.2.ISO, 1999).

Monitoring results during 2003 have shown that the limit value for human health protection 350 µg/m³ has not been exceeded, while during 2002 at Sacca Fisola station 4 exceedances have been found. SO₂ alarm threshold and the limit value for ecosystem protection have never been exceeded.

NO_X monitoring

Eight monitoring stations are provided with Nitrogen Oxides (NO_X) automatic analyzers: Parco Bissuola; via Bottenigo; Sacca Fisola; viale S. Marco; via Antonio Da Mestre; via Circonvallazione; Maerne; Malcontenta.

Instruments used for NO_X monitoring are located inside the monitoring stations and are based on the Chemiluminescence method (in compliance with the reference method of EU Directives ISO 7996:1985).

Monitoring results during 2003 have shown that annual average concentration of NO₂ has exceeded the annual limit value for human health protection (40 µg/m³) in seven monitoring stations, except via A. Da Mestre.

Pollutant has moreover presented two exceeding days of the 200 µg/m³ limit value at Parco Bissuola and via A. Da Mestre station. No alarm threshold exceedance has been recorded.

O₃ monitoring

Four monitoring stations are provided with Ozone (O₃) automatic analyzers: Parco Bissuola; via Bottenigo; Sacca Fisola; Maerne.

Instruments used for O₃ monitoring are located inside the monitoring stations and are based on the UV Photometric method (in compliance with the reference method of EU Directives ISO FDIS 13964).

In all stations monitoring results during 2003 have shown that ozone presented a number of exceedances of the attention levels (180 µg/m³, fixed by a National Decree) greater than the one found during 2002.

During 2003 health and vegetation protection levels have been also exceeded more than in 2002, while alarm threshold (360 µg/m³) has not been overcome.

Repeated exceedances of those values happened from 14.00 to 20.00 on 7-14 June, 20-22 and 26-28 July, 4-11 and 22-23 August, 19-22 September 2003. These levels, above all in the second week of June and August, correspond to intense solar radiation and high temperatures that helped ozone concentrations increase. Acute pollution episodes happened contemporarily in Maerne and Parco Bissuola monitoring stations.

In 2003 Ozone has exceeded human health protection levels for a greater number of days, contradicting the 2001 and 2002 trends.

Lead monitoring

Lead and other Heavy Metals concentrations in atmospheric PM₁₀ is monitored in three urban stations: Parco Bissuola; via Antonio Da Mestre; via Circonvallazione.

After PM₁₀ collection, its Lead concentration is measured in laboratory by using the ICP-MS (Inductively Coupled Plasma – Mass Spectrometry) analytical technique. This method in compliance with the reference method of EU Directives.

In all monitoring stations results during 2003 have shown that Lead annual average value is lower than the limit value (0.5 µg/m³). There is also evidence of Lead “seasonal” behaviour, with greater concentrations in autumn and winter seasons.

Last Updated

25th January 2005