The latest Version of DMRB

1. DMRB - Air Quality
Nigel Bellamy
DMUG 2016

2. Outline
 Highways England Guidance
 DMRB Assessment Best Practice
– Traffic Data
– Monitoring
– Modelling
 New DMRB AQ Model Tools Overview

3. Highways England Guidance Updates

4. Highways England Guidance Updates
Timeline since HA207/07
20092007 2011 2012 2013 2014
DMRB AQ
Chapter
HA207/07
LAQM (TG09)
IAN 170/12
Long Term
Trends
IAN 174/13 Advice
on Significance
EFT v4 EFT v5
Defra’s Report
on NOx & NO2
Trends
2015
IAN 185/15 Link
Speeds & Speed
Bands released
IAN 175/13
Compliance Risk
Assessment
EFT v6EFT v5.2
2016
LAQM
TG(16)

5. Highways England Guidance Updates
• Drive early collaboration between Traffic and AQ Teams;
• Identify risks at an early stage;
• Work to mitigate risk where possible, although this is an ongoing process
through the assessment;
• Monitoring to inform risks and to evaluate mitigation measure effectiveness;
• Proportionality of assessment whilst ensuring assessment is Robust;
• Right modelling for the assessment.

6. Highways England Guidance Updates
• Needs to be more Risk Based;
• Guidance to include flow charts to aid the user in relation to what the
assessment requires;
• Ensure that the AQ assessments are proportionate to the risk;
• Greater emphasis on mitigation.

7. DMRB Assessment Best Practice

8. DMRB Assessment Best Practice
 Traffic Data
• Fit for purpose
• Study Area
• Time Periods
• Scenarios
• Data Requests
• Check & Challenge

9. DMRB Assessment Best Practice
 Monitoring
– Programmed early
– Critical to verification
– Targeted coverage
• AQ Risk
• Dispersion characteristics
• Gradients
• Backgrounds
• Habitat sites
• Co-location
 Targeted coverage
– On-going review

10. DMRB Assessment Best Practice
 Monitoring Safety
– Risk Assessments
– Working at Height
– Lone Working
– Chapter 8
– MAC Inductions
– Weather
Bad site pic

11. DMRB Assessment Best Practice
 Air Quality Modelling - Emissions
– Diurnal emissions profile important
– Meteorology vs emissions
– Traffic flows vs HDVs

12. AM: 07:10:00
IP: 10:00 – 16:00
PM: 16:00 – 19:00
OP: 19:00 – 07:00
DMRB Assessment Best Practice
 Air Quality Modelling - Emissions
– 4 Periods
– Temporal emissions profile
– Direct representation of traffic models
– Enables mitigation modelling
AM: 07:10:00
IP: 10:00 – 16:00
PM: 16:00 – 19:00
OP: 19:00 – 07:00
AM: 07:10:00
IP: 10:00 – 16:00
PM: 16:00 – 19:00
OP: 19:00 – 07:00
AM: 07:10:00
IP: 10:00 – 16:00
PM: 16:00 – 19:00
OP: 19:00 – 07:00
AM: 07:10:00
IP: 10:00 – 16:00
PM: 16:00 – 19:00
OP: 19:00 – 07:00

13. DMRB Assessment Best Practice
 Air Quality Modelling - Emissions
– Emissions & Highways England Speed Bands
– Recognition that model speeds are uncertain
– Professional judgement on application of bands by traffic team

14. DMRB Assessment Best Practice
 Air Quality Modelling - Receptors
– What to include?
– Use appropriate OS data
– IAN174/13 Significance criteria requires
ALL receptors in exceedence to be
included

15. DMRB Assessment Best Practice
 Air Quality Modelling - Verification
– Model performance over large study areas can vary.
E.g. Motorway / Urban roads / Hotspots
– Highways England apply zonal verification where model
performance groups can be identified

16. New DMRB Tool Overview

17. New DMRB Tool Overview
• Updates the current version and will be more sophisticated;
• Contains the latest emission factors and speed band methodology;
• The outputs of the model have been validated at a large number of
sites in the UK;
• Allows input of detailed temporal traffic breakdowns (AADT, AAWT &
Period Flows);
• A GIS interface will allow the user to input receptors and roads.

18. New DMRB Tool Overview
Speed Bands
AADT
AAWT
AM, IP, PM & OP

19. New DMRB Tool Overview
• Draw Road – draw new roads as lines
• Edit Road – edit road positions
• Draw Receptor – draw new receptors as points
• Edit Receptor – edit receptor locations
• Draw Junction – draw junctions
• Edit Junction – edit junction locations
• Select Layer – Selects Layer in GIS for editing
• Delete – select and delete roads or receptors
• Roads – review all user defined roads and their associated receptors
• Audit – calculate distances between all roads and receptors and ascertain which roads are close enough to
receptors to have an influence on air quality. Enables a review of roads and junctions that influence each receptor.
• Export – export your roads and receptor data in a format to enable direct importing into the DMRB air quality
model
• Import – enables visualisation of air quality model results

20. Highlighted receptor – associated
roads are shown in yellow on map
and in table.
Select whether to include as
source.
New DMRB Tool Overview
Source selection & auditing – by receptor

21. Selected road is highlighted in
yellow
All receptors within distance
threshold highlighted in red.
New DMRB Tool Overview
Source selection & auditing – by road

22. Thank you & Questions