The anti-pollution travel pass is valid only on days of peak pollution.
The sale of such passes opens once the Prefect of the City of Paris announces the decision to reduce traffic in a press release and/or on the Prefecture of Police website, or by decision of Île-de-France Mobilités to apply the specific rate.

Sales of anti-pollution travel passes open the day before the peak pollution period. These passes can be used on the entire network of the Île-de-France region, and allows you to travel:

• on the regular public transport lines, including Orlybus and Roissybus, and Noctilien and Filéo night buses as well as on certain local services and transport on demand,
• TER or Intercity trains (except those that require reservation) in 2nd class.

The routes must be entirely completed in the Île-de-France region. It is not valid on Orlyval, the TGV, or on lines that do not apply the Île-de-France pricing (in particular the shuttles serving Le Bus Direct and VEA Disney airports and the OpenTour and Cars Rouges tourist buses).
 

Anti-pollution travel passes can be purchased the day before the peak pollution period.

They can be purchased and loaded:

• On a Navigo, Navigo Découverte, Navigo Annuel, Navigo Easy pass, Navigo imagines R: at all our sales counters through an agent, or on all our automatic ticketing machines;
• In RATP-approved shops .
• On your phone from The "Bonjour RATP" application

  

   

The anti-pollution travel pass is valid for one day, which the user chooses during purchase, over the defined peak pollution period. It is valid from 12 a.m. to 11:59 p.m. on the chosen day.

For the Noctilien bus network, the anti-pollution travel pass is valid until 5:59 a.m. the day after it is valid. The time taken into consideration is the time the pass is validated for the first time.

The anti-pollution travel pass is sold individually at a single price.
As of 1 July 2021, the price of the anti-pollution package is €3.80.