Peters & Peters

ASA considers whether TFL’s claims about the Ultra Low Emission Zone were likely to mislead


Key facts:

The ASA received over 500 complaints about a series of TV, radio and press adverts for Transport For London’s (TFL’s) Ultra Low Emission Zone (ULEZ). The adverts claimed that “London has an urgent air quality problem” and that ULEZ expansion would “help clear London’s air” and referred to statistics around air pollution and the effect of the ULEZ. In response to the ASA’s investigation, TFL referred to various reports about deaths attributed to air pollution in London and the environmental health risk of air pollution.

The ASA upheld two complaints but rejected three complaints:

  1. Complaints about the claim “London has an urgent air quality problem and it is impacting the health of Londoners” were not upheld. The ASA thought that it was reasonable for TFL to make this claim based on the evidence.
  2. Complaints about claims that the ULEZ would “help clean the city’s air” were not upheld. TFL had forecasted the likely effect of ULEZ expansion on road traffic and emissions. While the data indicated some improvement in relation to all air quality factors, the advert did not claim that the ULEZ would be the single factor to improve air quality overall. The ASA concluded that claims that the ULEZ extension would help improve air quality were unlikely to mislead.
  3. Complaints about claims that nitrogen dioxide (NO2) had reduced by almost a half since the implementation of the ULEZ in Central London were upheld. TFL’s calculations were based on the difference between a non-ULEZ and a ULEZ scenario, rather than based on air quality sampling before the introduction of the charges and after the implementation of the ULEZ. The ASA found that clear qualification was required in order to ensure that TFL’s claims would be fully understood, which was lacking. The claims in the adverts would therefore be likely to mislead.
  4. Complaints about references to air pollution deaths in “Outer London” were upheld. While the evidence indicated that the mortality burden in Outer London was greater than that of Inner London, the advert did not clarify that the claim “most air pollution related deaths actually occur in Outer London areas” was based on modelled estimates, using the latest available data, and not actual deaths. The ASA found that because the basis of the claim was not explained, and evidence to support the claim was not supplied, the advert was likely to mislead.
  5. Complaints about the claim that “recent reports have shown a link between air pollution and an increased risk of developing dementia” were not upheld. Based on the evidence, the ASA found that this claim was unlikely to mislead the public.

The ASA told TFL to ensure that the basis of all environmental claims was made clear in future adverts.


ASA ruling

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