Headroom in new subways should be a minimum of 2.4m. Existing subways with lower headroom have been successfully converted to cycle use but should be risk assessed and warning signs added where appropriate (see also A15 Audits and Risk Assessment). Signs should be mounted at least 2.3m above the surface of a cycle track.
Designers should aim to achieve a maximum gradient of 3% with the absolute maximum 5% for lengths up to 100m. On the approach to priority junctions this should not exceed 3%. Where steeper slopes are unavoidable the limiting gradient is 7% for lengths up to 30m.
