Traffic NO2 Overlay

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Traffic NO2 Overlay

The Traffic NO2 Overlay is a Grid Overlay which computes the impact of traffic air pollution (in μg/m³ NO2) for any given location in the project. The calculation takes into account the amount of traffic per type and the distance from the source of emission. It also takes into account objects and terrain features which would hinder the travel of particles.

The Overlay only takes into account NO2 emissions from traffic. Other sources of emissions (such as air traffic of factories) are explicitly excluded.

The Overlay implements SRM1[1], which is only applicable for urban environments.

Traffic NO2 Model


Main article: Model attributes (Traffic NO2 Overlay)

The Traffic NO2 Overlay has a number of options which allow it to be configured as desired. A configuration wizard is available.

The following aspects can be configured:

  • Base concentrations of NO2 and NOx
  • Emissions per vehicle type both in motion and in traffic jam
  • Constants for road-based dilution factors
  • The hour(s) of the day to perform the calculation for


Traffic intensities for each type of traffic can be based on one of the following:

The traffic intensities can be defined as either a single value or as 24 hours, with each value corresponding to each hour of the day. The intensity used for the calculation is then defined by the HOURS model Attribute.


Main article: Traffic NO2 formula (Traffic NO2 Overlay)

The Traffic NO2 Overlay performs its calculations based on the Overlay's Attributes, the presence of trees, and the Attributes of roads present in the project. The calculations follow the standard rekenmethode 1 (SRM 1)[1].


The following result types are available as output from the traffic NO2 calculations:


  • The Overlay calculations are based on Standard Calculation Method 1 (SRM1) as defined by the dutch government.[1].



  1. 1.0 1.1 1.2 SRM1 ∙ Regeling beoordeling luchtkwaliteit 2007, Bijlage I ∙ Found at: ∙ (last visited: 16-02-2022)