The application and inclusion of monetary valuations on casualties and accidents of differing severity is now standard in UK cost-benefit analysis; however, within the STAG Appraisal, the monetary value should not be included in the TEE analysis, which is solely for economic impacts (See Section 12.7 - Headline indicators in STAG). In transport appraisal, accidents can impose a wide range of impacts on people and organisations including medical and healthcare costs, losses in economic output, material damage, emergency services costs, insurance and legal costs and, more controversially, an allowance for the pain, grief and suffering incurred. In some cases there is concern with the direct safety performance of the system, it is therefore helpful to estimate accident numbers directly as well.
Practitioners are advised to consider whether the option under consideration will have any measurable impact on the number of transport related accidents and/or their severity.
If measurable changes to accident numbers and/or severity are identified as important impacts of an option, then practitioners are advised to adopt well established methodologies to aid the quantification of road traffic accidents and only in exceptional circumstances to depart from such methodologies.
For a rail-based public transport scheme practitioners should assume, in the first instance, that accidents associated with the option are negligible. For public transport options that involve shared running, practitioners should seek the advice from the Scottish Government and/or its agency Transport Scotland. For maritime and aviation options, practitioners should seek the advice of the respective safety agency.
