1. The Panel recommends that in future, schemes that modify the form of a road should only be for these four purposes:

• Shifting trips to sustainable transport to reduce carbon emissions
• Reducing casualties where they are high, through small-scale changes
• Adapting roads to the impacts of climate change
• Supporting prosperity by providing access to development sites that will achieve high sustainable transport mode share

2. The Panel recommends that road schemes that are consistent with current policy (i.e. schemes that achieve mode shift, reduce casualties, adapt roads to impacts of climate change, or provide access to development sites that will achieve high sustainable transport mode share) should meet four conditions:

• The scheme should minimise carbon emissions in construction
• The scheme should not increase road capacity for cars
• The scheme should not lead to higher vehicle speeds that increase emissions
• The scheme should not adversely affect ecologically valuable sites

5.4 The Panel considered that capital enhancements that change road or junction layouts may be appropriate where there are concerns in relation to safety, evidenced by a significantly higher rate of personal injury collisions than anticipated for the type of road, traffic volume or location.

However, before making changes to a road or junction layout, non-infrastructure measures to reduce casualties should be fully appraised, including lower speed limits; speed enforcement; enhanced road markings; and warning and other signs. These measures may achieve a sufficiently large reduction in casualties, and be more cost effective than changes to the road or junction layout. Speed limit reduction can provide a safety benefit over the length of a route, and may complement even lower limits at discrete locations. These measures also have low or zero embodied carbon emissions; and measures to reduce speeds have the added benefit that they reduce carbon dioxide emissions in use. Evidence should be provided that these non-infrastructure interventions are not as effective as required before beginning to consider more significant infrastructure interventions.

When appraising schemes that reduce speeds to improve safety, the Panel recommends that the resulting small increases in journey time should not be treated as a disbenefit in cost-benefit calculations. This will remove the possibility that safety is traded against journey time reductions in appraisal.

Where changes to road or junction layouts are necessary, the Sustainable Transport Hierarchy should be used to inform design development and decision- making. This means that priority must be given to changes to layout that reduce risk for people walking and cycling (who are at higher risk of death or serious injury) while providing more direct and convenient routes for these road users.

The above recommendations relate to capital safety enhancements, which change the form of the road asset, and not to routine maintenance and asset renewal which change its condition.

The Lugg Review of "Strategic Road Network Programmes in Relation to Meeting Statutory Duties" makes recommendations as to how the "safety-critical elements" of maintenance and asset renewal programmes should be prioritised and progressed.

Setting an objective to reduce road casualties does not, on its own, make a scheme consistent with current policy. An assessment is needed as to whether the scheme, in its entirety, is the most effective option to achieve that objective, and whether it may have the unintended effect of making other policy aims, particularly in relation to modal shift and carbon emissions, more difficult to achieve.