Cambridge Environmental Research Consultants (CERC)

- Advanced Screening Tool for Industrial Emissions

From

ADMS-Screen is a screening model for air quality calculations. It models dispersion from a single stack to calculate ground-level concentrations, providing rapid assessments of stack height. Comparison with air quality strategy objectives and European Union air quality standards can be made. The model also has an option to include building effects. It can be used to indicate whether further modelling is required. ADMS-Screen uses the ADMS dispersion code, includes the ADMS Mapper for GIS visualisation and editing, plus a line plotting facility and optional link to Surfer for contour plotting.

ADMS-Screen is used by government bodies, private organisations and universities across the United Kingdom, and in other countries across the world, to provide a quick assessment of the impact of point source emissions.

ADMS-Screen is an easy-to-use tool for the rapid assessment of the air quality impact of a single industrial stack. It combines the state-of-the-art dispersion modelling algorithms of the ADMS models with a simple user interface requiring minimal input data.

Applications include:

  • initial assessment to determine whether more detailed modelling is required,
  • stack height determination,
  • environmental impact assessments, and
  • safety and emergency planning.

Buildings

The dispersion of air pollution around buildings is complicated to model. The building effects module in ADMS-Screen is a reduced version of that of ADMS 4 to that extent it only models one building instead of many. It includes the following features.

One building can be included in each model run. For each wind direction, a single effective wind-aligned building is defined, around which the flow is modelled.

The flow field consists of a recirculating region (or cavity), with a diminishing turbulent wake downstream.

Concentrations within the cavity, CR, are uniform, and based on the fraction of the release that is entrained. The concentration at a point further downwind is the sum of contributions from two plumes: a ground-based plume from the recirculating flow region and an elevated plume from the non-entrained remainder. The concentration and deposition are set to zero within the user-defined building.

  • All input data are entered via a single screen.
  • ADMS-Screen is available containing a built-in data set of meteorological data for one of the following three countries: United Kingdom, China and Latvia. For each of these countries, meteorological data for a number of regions is included. If you wish to use ADMS-Screen with meteorological data for a country not listed here, please contact us for further information.
  • ADMS-Screen includes the capability to model the effect on dispersion of a building in the vicinity of the stack.

  • Both short term results (separate results for each meteorological condition) and long term results (statistics such as annual mean and percentile concentrations) can be calculated.
  • Short term results are calculated for a range of typical meteorological conditions. ADMS-Screen includes an integral line plotting facility to display the results.
  • ADMS-Screen can produce long term output for direct comparison with national and international air quality standards at the click of a button.
  • ADMS-Screen includes a link to Surfer to display contour plots of long term output. The output files are also formatted in such a way that users without Surfer can easily produce contour plots in Excel.

Example contour plot of ADMS-Screen output, created in Surfer.

The model interface is designed so that the user can enter the data required for the modelling in as straightforward a way as possible.

The interface consists of several main screens. To set up a model run, the user simply works through the screens entering the relevant data or referencing external data files.

ADMS-Screen is supplied with an in-depth user guide (see the User guides page) that details all user inputs and outputs, and includes a number of step-by-step worked examples.

An annual maintenance contract provides support for users; this includes:

  • maintenance model upgrades,
  • use of the helpdesk by e-mail, phone, fax or post.

Current versions and system requirements

  • Current software versions and release dates are listed here.
  • System requirements and compatibility with third-party software are described on the System requirements page.