Modelling

From this page you can access the following tools, related to air quality modelling and screening.

Guidance on the DMRB Screening Model

The Design Manual for Roads and Bridges (DMRB) Screening Model is a screening tool published by Highways England (formerly the Highways Agency) that can be used to predict pollutant concentrations at receptor locations near to roads.

Whilst Highways England is updating the DMRB and has redesigned the Screening Model, it is not currently on public release. Therefore, whilst the Screening Model v1.03c has been withdrawn by the Highways Agency, it can still provide for a useful way to screen road traffic emissions to decide whether more detailed dispersion modelling needs to be undertaken, but results should be treated with caution particularly where predicted concentrations are close to the relevant Air Quality Objectives.

Application of suitable model verification and the Gap Analysis approach as discussed in Highways England’s Interim Advice Note IAN 170/12 will help to improve the confidence of the Screening Model v1.03c predictions. Guidance on using the DMRB can be viewed via the link below, whilst the LAQM Helpdesk can be contacted for further advice.


DMRB guidance (PDF 59Kb)

Supplementary Assistance Spreadsheet for Stack Height Calculation

A chimney height calculation spreadsheet for sulphur dioxide emissions from small boilers is available.
Download the spreadsheet (XLS 80Kb).

Also, a report giving supplementary assistance on stack height determination in relation to sulphur dioxide emissions from small boilers can be downloaded Supplementary Assistance on Stack Height Determination (PDF 50Kb).

Calculators for Industrial Nomograms and Biomass Nomograms

An Excel screening tool based on a series of nomograms developed as part of previous versions of LAQM Technical Guidance which are still considered relevant. The Industrial Emissions Screening Tool is provided under emissions tools.

Information on how the screening criteria for Review and Assessment of Airports was derived.

A report which describes how the criteria for screening set out in TG(16) was derived is available here.

Note on Projecting NO2 Concentrations

The LAQM Helpdesk previously published a Frequently Asked Question (FAQ) in relation to trends of NOx and/or NO2 concentrations. This FAQ highlighted that recent monitoring data suggests that reductions in NOx and NO2 concentrations have been much smaller than forecast. The FAQ suggests that on some occasions local authorities may wish to consider the emerging information in relation to future predictions when producing their statutory reports. This note provides some further information on the alternative methods that might be useful for local authorities to consider in the interim whilst awaiting updates to currently available methods. This note is available on request and is not part of the Technical Guidance for Local Air Quality Management 2016 and as such does not form statutory guidance.