Indice Qualité de l'Air
La qualité de l’air sur la Principauté est exprimée grâce à un indice journalier global calculé à partir des données mesurées par les stations de qualité de l’air opérées par la Direction de l’Environnement.
The Air Quality Index (AQI)
Within the framework of the partnership between the Principality and AtmoSud, air quality in the Principality is expressed using an overall index from 0 (very good) to 100 (alert threshold), calculated on the basis of data collected by the 5 air quality measuring stations operated by the Department of the Environment.
The AQI forecast for the next day (D+1) is also estimated, taking weather forecasts into account.
Calculating the Air Quality Index
A calculation of this index is obtained by estimating the concentration of five pollutants: nitrogen dioxide (NO2), fine particulate matter (PM10 et PM2.5), sulphur dioxide (SO2) and ozone (O3). These pollutants are good indicators of the air pollution to which the population is exposed in urban areas.
For each pollutant, a sub-index is calculated according to a specific concentration range. Air quality is defined by the maximum (i.e. the worst) of these five sub-indices, with the following ratings:
Concentrations des polluants estimées en µg/m 3
Estimated pollutant concentrations in µg/m3
Information and alert thresholds
The thresholds for informing and alerting the public remain unchanged.
Information-recommendation threshold: concentration level at which information and recommendations are relayed to the population.
Alert threshold: concentration level higher than the information thresholds, at which emergency measures to reduce pollution are implemented.
Niveau de concentrations à partir duquel une information et des recommandations sont relayées à la population