The document summarizes progress on Clean Air Zones in the UK. It outlines that the UK has been in breach of legal limits for nitrogen dioxide and discusses the need for immediate action to improve air quality and health. It defines Clean Air Zones as areas with restrictions on certain vehicles to encourage cleaner vehicles. Authorities need to develop local plans with measures to achieve compliance, which requires modeling emissions and impacts. Options being considered by authorities include charges for different vehicle types in Clean Air Zones of varying sizes and stringency. Authorities are at different stages with some publishing initial plans focusing on buses, taxis, HGVs or LGVs. The overall progress aims to achieve compliance with legal limits as soon as possible to reduce human exposure

1. Routes to Clean Air
Clean Air Zones -
A Summary of Progress
Nigel Bellamy
30 Oct 2018

2. Outline
• Why Clean Air now?
• Defining a Clean Air Plan
• What does an Authority need to do?
• Appraisal Process
• Authorities Progress

3. Why Clean Air Now?
• UK has been in breach of the legal Limit Values regarding levels of NO2 in major urban areas.

4. Title

5. What is a Clean Air Zone?
• Text
Supporting local
growth and
ambition
Accelerating
transition to a
low emission
economy
Immediate
action to
improve air
quality and
health
Clean Air Zone
Access restrictions to encourage cleaner vehicles

6. What CAZ measures?
Understand the problem:
– What is ‘Compliance’?
– Magnitude & Locations
– Sources
– Urban centre vs Strategic route
Design Measures to achieve compliance:
– Deliverable?
– Quantifiable?
– …acceptable?
– Charging-CAZ only appropriate if
other measures don’t deliver
BUT must be used as the benchmark
scenario
The three legal tests for assessing air quality plans
Local plans must:
1. Aim to achieve compliance as soon as possible;
2. Choose a route to compliance which reduces human exposure
as quickly as possible; and
3. Ensure that compliance with the limit values is not just
possible but likely.
(ClientEarth (No. 2) -v- The Secretary of State for the Environment, Food and Rural Affairs [2016] EWHC 2740)
A CAZ
should achieve
compliance by
focusing on
3 specific outcomes:

7. Charging-CAZ Criteria
Defra Charging-CAZ Classes
Vehicle
Type
Proposed CAZ Charges
Low Medium High
Car £3 £6 £12.50
Taxi £3 £6 £12.50
LGV £3 £6 £12.50
HGV/Bus/
Coach
£25 £50 £100
Example CAZ Charging Rates
Vehicle Type Compliant Class
Car/Taxi
Diesel Euro 6 (2015)
Petrol Euro 4 (2005)
Van Euro 6 (2016)
Bus/HGV Euro VI (2013)
Age of Compliant Vehicles
The aim of a charging-CAZ is
that no drivers pay.
(i.e. not a congestion charge).

8. What Does an Authority
need to do?
• Produce a Local Plan i.e. a Full Business Case
– Treasury Green Book - 5 Case
• What is success?
• Develop measures
• Approvals
• Consultation
• Mitigation
• Implement

9. Outline Business Case
• Text
Case Elements to be Included
Strategic Case Policy Context
Case of Change
Summary of Results of Modelling
Economic Case Costs and Benefits assessed for Each Option – Estimate
NPV
Distributional Analysis of Options
Report on Options Appraisal including Non-Monetised
Impacts and Determination of Preferred Option.
Commercial Case Procurement Strategy
Timescales for Preferred Option begin to be progressed
Financial Case High-Level Costing of all Options
Financial Profile of Options
Potential Funding Mechanisms / Other Funding Sources
Management Case Programme Planning and Management for Delivery
Benefits Realisation Strategy
Consultation Strategy
Complete OBC Bring 5 Cases Together into One Coherent Case
Methodology Reports & Sensitivity Analysis in Appendix

10. Example Short Listed Measures
• Text
Potential Measures
CAZ – Differing Class and/or geographical
boundaries
Manage Congestion
Differential parking charges Incentivise hackney carriages/PHV EV uptake
and expand charging network
Retrofit or upgrade of public transport fleet;
stringent emissions standards
Retrofit hackney carriages
Public Transport Capacity increases Communication/awareness campaigns
Bus/HGV/LGV – switch to GtL Travel choices programmes (businesses &
individuals)
EV incentivisation Active Travel – infrastructure/engagement
Retrofit/upgrade LA fleet

11. Preliminary Information
• Text

12. Initial
Evidence -
2021
• Source
Apportionment
• Analyse the cause of
emissions for each
location
• Differences
depending on nature
of Origin-Destination
• Screening calcs of
potential measures
• Design packages
measures
** These are sites adjacent
to the HE network as
classified by TfGM, but
responsibility for tackling
these sites is still to be
defined.

13. Fleet Analysis
Vehicle Type % Compliant
Car 79%
Hackney Cab 38%
Private Hire Taxi 73%
LGV 58%
HGV 71%
Bus 30%*
Proportion of Vehicle Predicted to Comply with CAZ criteria in 2021

14. Options Appraisal
Measure
Definition
• Define measure & assumptions
• Significant impacts to behavior/demand/emissions?
Demand
Model
• Changes to travel demand inc. modes/PT
• Significant change to trips?
Assignment
Model
• Defines routes for trips
• Changes on specific roads?
Emissions
Model
• Calculates emissions on each road
• Gap calculation predicts possible impacts
Dispersion
Model
• Disperses emissions
• NO2 concentrations
Screen out
or refine
Options
Appraisal
• Achieves compliance?
• Analysis of impacts

15. Describing the Impacts
Providing Decision Makers with suitable information…
… the Business Case doesn’t by default.
WHY: Health & legal responsibility
WHAT: Range of schemes tested (and what won’t be effective)
WHEN: ….
WHO & WHERE: Distributional Analysis:
• How many people/businesses affected
• Health benefits
• Equalities
HOW: Need to mitigate the adversely effected

16. Potential Information from core
modelling
• What change is generated by a scheme:
 Number of vehicles that upgrade – can assess costs of this
 Number of vehicles that stay and pay – and revenue generated
 Number of vehicles that change their trip, what mode they shift to & the costs/benefits of this
 Number of vehicles that cancel their trip
• Highway network impacts i.e.: changes in traffic flow, mode, composition or speeds
• Emissions reductions (NOx, PM, Carbon) and change in the number/level of exceedances by location
• This meets the JAQU requirements for a compliant business case but will not answer all our questions

17. What other information might
be available?
• Range of measures in a Short List inc. Benchmark CAZ scenario means that we have to cover a wide
range of measures.
• Summarising the socio-economic impacts spatially
• Case study analysis for particular groups and places of interest, covering:
 Businesses by size
 Low paid workers
 Taxi and PHV drivers
 Key sectors: retail, leisure & services, logistics & transportation
 Economic hubs: city centre, other economic hubs beyond the centre
 Impact on providing council services
 Impact on providing bus services
 Drivers by vehicle type
• A summary narrative report drawing together all the evidence into an accessible, easy-to-read report
that takes people on the policy journey

18. Known Issues?
• Responses to pricing
• Diesel vs petrol car sales trends
• Transport modelling validation over large study areas
• Real-world emissions inc f-NO2
• Availability of compliant vehicles
• Transport disruptions
• Administration of mitigations/exemptions
• Informing business/public

19. Authority Progress
Type of
Measures
Publishing Authorities (SOC or OBC)
A
Buses/Taxis
Derby
Nottingham
York
Leicester
B
HGVs
Leeds
Southampton
Sheffield
C
LGVs
Bristol
D
Cars
London
Birmingham
Bath
Oxford
Indicative Measures
https://www.fleetnews.co.uk/fleet-faq/what-are-the-proposed-uk-clean-air-zones-caz

20. Thank you

21. Head Office
23 Coldharbour Road, Bristol BS6 7JT
Tel: 0117 974 1086
London Office
119 Marylebone Road, London NW1 5PU
Tel: 020 3873 4780