Model Guidelines

Guidelines for the Preparation of Short Range Dispersion Modelling Assessments for Compliance with Regulatory Requirements – An Update to the ADMLC 2004 Guidance

In 1995 the Royal Meteorological Society (RMetS) produced a set of guidelines which were intended to promote the use of best practice in the use of mathematical models of atmospheric dispersion, emphasising the principle of fitness for purpose in the selection of modelling procedures, and the importance of effective communication in the documentation of reported results.

This guidance was updated in 2004 by ADMLC (ADMLC, 2004) as agreed with RMetS and now the current document has been produced to take account of modelling and regulatory changes over the intervening years (ADMLC-R12, 2021).

The intention of this report is to guide professional air quality workers in the production of robust assessments by the careful consideration of the context, and the selection and justification of appropriate models and input data. It also advises on general methods of communicating the results of the assessment and considerations of variability, sensitivity and uncertainty. Recommendations are made for the recording of results and decisions in the form of an audit trail to aid subsequent inspection of the assessment process by third parties. Some specific areas where assessments are frequently found to be weak are addressed in a series of appendices.

The RMetS has agreed to the preparation of this revised guidance.