Guidance

Air quality: impact pathway guidance

Guidance on impact pathway approach for valuing changes in air quality.

• From: Department for Environment, Food & Rural Affairs
• Published: 10 May 2013
• Last updated: 14 January 2019 — See all updates

This publication was withdrawn on 25 March 2020

This guidance has been replaced. See current guidance on assessing the impact of air quality.

Documents

Impact pathway guidance for valuing changes in air quality

Ref: PB14536

PDF, 3.53 MB, 24 pages

Details

This guidance provides an overview of the impact pathway methodology, which is the central methodology for valuing changes in air quality.

It values the air quality effects of proposed decisions by estimating how changes in the ambient concentrations of air pollutants affect a range of health and environmental outcomes.

This guidance sets out best practice appraisal methodologies for all projects, programmes and policies. The impact pathway approach has been developed by Defra with support from the Interdepartmental Group on Costs and Benefits (IGCB), a Defra-led group of government analysts that provides advice relating to the quantification and valuation of local environmental effects.

Published 10 May 2013
Last updated 14 January 2019 + show all updates

1. 14 January 2019

   Updated the guidance.

2. 12 September 2015

   Added link to the interim guidance for health impact of emissions of NOx and concentrations of NO₂.

3. 10 May 2013

   First published.