A blog post by Favour Agunu, Senior Associate

The Crit’Air policy in Paris was implemented to control emissions level and operate Low Emission Zones (LEZ) in the city.[1] Crit’Air refers to the commercial name for the “Certificat qualite’ de l’air” which means “Air Quality Certificate.[2] This certificate, introduced by France on June 21, 2016, serves the purpose of identifying the emissions level of each vehicle and depending on the emissions, restricting access to specified LEZ’s.[3] In France, Paris was the first city to introduce a LEZ and currently applies access restrictions to the City of Paris and the Greater Paris Region.[4]Generally, LEZs are applied in densely populated cities to “regulate the entry of high-emitting vehicles.”[5] Paris was one of those cities that had suffered the high impacts of transport exhaust emissions, such as the premature death of its citizens, made more severe by its dense population.[6]

            Various studies have revealed that LEZs are effective in reducing emission concentrations, provided there are stringent restrictions applied to vehicles entering the LEZ.[7] Paris introduced its LEZ under a five-phase roll-out schedule that planned to restrict all vehicles emitting exhaust by 2030.[8] Crit’Air is one of the main means through which Paris has decided to apply these restrictions. Each phase of the Paris LEZ policy aims to restrict a new category of vehicle within the LEZ.[9] The different categories have designated Crit’Air numbers from one to five depending on the vehicle’s engine type and Euro standard.[10] Phase one came into effect in 2017 by restricting the entry of Crit’Air 5 vehicles as well as vehicles deemed unclassified.[11] This was extended to Crit’Air 4 vehicles in 2019.[12] The last phase plans to grant entry to only Crit’Air green vehicles which are electric or hydrogen vehicles emitting no exhaust related pollutants.[13] It has been projected that as more stringent entrance requirements are implemented in Paris, “passenger car NOx emissions in 2024 will be 76% to 87% below the levels at 2016”.[14]

            While the adverse effects of air pollution on public health cannot be overstated, the implementation of LEZ policies, such as Crit’Air, may pose challenges for lower income citizens and small businesses.[15] These citizens may find it difficult to comply with more stringent policies as they lack the financial capacity to switch to cleaner vehicles which will probably be necessary due to the likelihood that they own affordable high-polluting vehicles.[16] The inequity becomes more critical when taking into consideration the fact that these lower income group contributes the least to vehicle emissions but are nevertheless exposed to more than average levels of transport related air pollution.[17] Other equity considerations include gentrification, employment mobility and impact on access to public transportation.[18]

            To address the above socio-economic challenges, Paris’ Crit’Air policy attempts to provide some targeted incentives such as allowances of 6000 to 9000 euros to small businesses willing to switch to cleaner vehicles and additional support to lower-income households.[19] However, it is recommended that more schemes be developed, such as promoting alternative clean forms of mobility and creating special rules for lower income households.[20]

[1] Yoann Bernard et al., Impacts of the Paris low-emission zone and Implication Zone and Implications for other cities, The Real Urb. Emissions Initiative 1, 5 (2020), https://theicct.org/sites/default/files/publications/Paris-LEV-implications-03.12.2020.pdf

[2] All there is to know about the anti-pollution Crit’Air certificate in France, Renault Grp.  (Dec. 30, 2020), https://www.renaultgroup.com/en/news-on-air/news/all-there-is-to-know-about-the-anti-pollution-critair-certificate-in-france/.

[3] Yoann Bernard et al., supra note 1, at 5

[4] Mathew Beedham, Do low emission zones work? TomTom Traffic Index has the answer, tomtom (Feb 9, 2022), https://www.tomtom.com/newsroom/explainers-and-insights/do-low-emission-zones-work/.

[5] Yoann Bernard et al., supra note 1, at 5

[6] See Id. at 3 (associating transport emissions with a mortality rate of 11 citizens per 100,000 population in Paris).

[7] Erika Moreno et al., The environmental justice implications of the Paris low emission zone: a health and economic impact assessment, 15 Air Quality, Atmosphere & Health 2171, 2180 (2022)

[8] Id. at 2172.

[9] Id.

[10] Erika Moreno, The environmental justice implications of the Paris low emission zone: a health impact assessment, UC San Diego: Climate Sci. and Pol’y 1, 20 (2020), https://escholarship.org/uc/item/9pb9m7hb.

[11] Id.

[12] Id.

[13] Union of Concerned Scientists, Low- and Zero-Emissions Zones Opportunities and Challenges in Designing Equitable Transportation Policies, Union of Concerned Scientists 1, 7 (2021),

https://www.jstor.org/stable/resrep34181.

[14]  Id.

[15] Low-Emission Zones are a success – but they must now move to zero-emission mobility, Transp. & Env’t 1, 3 (2019), https://www.transportenvironment.org/wp-content/uploads/2021/07/2019_09_Briefing_LEZ-ZEZ_final.pdf. [hereinafter Transport & Environment]

[16] Erika Moreno et al., supra note 7, at 2180-81

[17] Id. at 2180.

[18] Id. at 2181.

[19] Transport & Environment, supra note 15, at 4

[20] Id.