Sadiq Khan has dismissed the idea of introducing a "24-hour cooldown" period for people driving non-compliant vehicles in the Ultra low emission zone (Ulez).
The proposal suggested making drivers effectively 'immune' from paying the charge for 24 hours after they last paid it - meaning night shift workers would no longer be at risk of paying more per week than people who work during the day.
But the Mayor said only a small number of night shift workers were affected by the charge in this way, and that other travel options, such as night buses, were available to them.
The Ulez, which expanded at the end of August to cover the whole of Greater London, means that older, more polluting vehicles have to pay a daily charge of £12.50.
The charging period resets at midnight each day, meaning that someone driving to work in the morning and back home in the afternoon only pays once per day - or five times per week, provided they do not use their car at weekends.
A shift worker working nights every day from Monday to Friday will pay the charge six times per week however, presuming that they return from their last shift of the week in the early hours of Saturday.
The issue was raised with mayor Sadiq Khan in a letter from Dr Onkar Sahota, Labour London Assembly Member for Ealing and Hillingdon.
Dr Sahota asked Mr Khan whether he will “consider a 24-hour cooldown between charges to allow these workers to commute to work and only pay the charge once?”
Responding, the mayor's office said that he “recognise[s] and appreciate[s] the contribution of London’s night-time workers” and that many of them will choose not to drive to work.
The written answer pointed out that only a small proportion of drivers in the capital use non-compliant cars. Data released at the end of October revealed that 95.3 per cent of vehicles seen driving on an average day in London are now compliant – up from 91.6 per cent in June.
This was higher for cars – 96.4 per cent of which are now not liable for the Ulez levy – but lower for vans at 86.2 per cent, though this was up from 80.2 per cent in June.
Mr Khan's office continued: “The impact of the London-wide Ulez on shift workers was covered in the independent Integrated Impact Assessment, which the Mayor considered before making his decision. Given the high level of compliance, only a very small number of night workers who drive are likely to be affected.
“To help those affected, mitigations including night bus and Tube services and a £160m scrappage scheme are in place. Every Londoner with an eligible non-compliant car or motorcycle can now apply for the scrappage scheme, meaning shift workers who were not previously eligible can receive financial support.
“Road user charging schemes are continually kept under review to ensure their ongoing effectiveness.”
The specific issue of night shift workers paying the Ulez charge twice was previously raised by Liberal Democrat mayoral candidate Rob Blackie, who said that if elected, he would look to make the charging system less “blunt” and “better targeted”.
