Standardised London Subground Signage

Standardised London Subground Signage (SLSS) is a signage system warning the citizens of London and surrounding areas of hazards arising from the flooding of areas situated below sea level (subground areas). SLSS signage describes the area, the risk of it flooding, and evacuation paths should flooding occur. It also provides the location of sump pumps and indicates the responsible party to inform, should they fail. Flood risk is defined as the probability and rate of an area flooding in the event of a pump failure, as well as the ease of access to exits. SLSS signage is legally required in subground areas with a flood risk higher than Low (1-3). The SLSS system was designed by the Thames Republic Department for Climate and Environment (DfCE) in cooperation with Greater London Authority (GLA) and the Lead Local Flood Authorities (LLFAs) of local boroughs.