TAG unit A3 environmental impact appraisal

Transport Analysis Guidance (TAG) on the analysis of environmental impacts in transport appraisals.


TAG unit A3 environmental impact appraisal

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This document gives guidance on environmental impact appraisal.

The air quality valuation workbook was updated in May 2019.

This Transport Analysis Guidance (TAG) unit was updated May 2019 to incorporate Defra released guidance on the valuation of transport-related air quality impacts, covering a range of different impact pathways and transport modes. A new workbook to aid in the calculation of monetised impacts of air quality was also published alongside this update.

The previous version of this unit was TAG unit A3 environmental impact appraisal, December 2015.

TAG provides information on the role of transport modelling and appraisal, and how the transport appraisal process supports the development of investment decisions and business cases.

Published 31 May 2019
Last updated 13 August 2019 + show all updates
  1. NO2 changed back to NOx in 3.2.7 following Department for Environment, Food & Rural Affairs clarification.
  2. Information updated for technical errors NOx changed from NO2 in 3.2.7 and 3.4.4.
  3. First published.