An unapologetically technical conference, DMUG remains the key annual event for experts in this field. Unmissable speakers will be examining topical issues in emissions, exposure and dispersion modelling.

1. Roger Barrowcliffe
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2. Vehicle emissions – what we know
and what we do currently….
 Measurements tell us that NOx emissions depend
principally on engine load, ie acceleration
 Microsimulation models provide a viable means of
modelling instantaneous emissions
For assessment of air quality we use:
 outputs from traffic models, ie volume and speed
 dispersion models with an averaging time of one
hour
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3. COPERT Emission Factors
(results taken from TfL measurements)
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4. Instantaneous NOx emissions
(results taken from Emissions Analytics)
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5. NOx emission by Flow State
(Joumard et al 2008)
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6. Dutch Approach to Emission Factors
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emission factors 2016 [g/km] Euro-6 RDE Euro-5
urban congestion NOx 0.679 0.314 1.000
NO2 0.288 0.129 0.327
urban normal NOx 0.571 0.244 0.708
NO2 0.225 0.100 0.214
urban free flow NOx 0.454 0.188 0.542
NO2 0.176 0.077 0.160
rural NOx 0.397 0.170 0.531
NO2 0.157 0.070 0.161
motorway average NOx 0.404 0.171 0.588
NO2 0.165 0.070 0.181
motorway congestion NOx 0.594 0.253 0.746
NO2 0.233 0.104 0.227
motorway strict 80 km/h speed limit NOx 0.310 0.127 0.405
NO2 0.122 0.052 0.122
motorway no strict 80 km/h speed limit NOx 0.312 0.185 0.466
NO2 0.095 0.046 0.152
motorway strict 100 km/h speed limit NOx 0.253 0.139 0.501
NO2 0.111 0.057 0.158
motorway no strict 100 km/h speed limit NOx 0.294 0.148 0.528
NO2 0.127 0.061 0.165
motorway 120 km/h speed limit NOx 0.377 0.166 0.576
NO2 0.156 0.068 0.178
motorway 130 km/h speed limit NOx 0.434 0.173 0.589
NO2 0.174 0.071 0.181

7. So, is there a better way of
estimating vehicle emission for
use in dispersion models?
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