This article is primarily concerned with accidents on the London Underground network, which carries around a billion passengers a year. Statistically, there is just one fatal accident for every 300 million journeys. There are several safety warnings given to passengers, such as the traditional 'mind the gap' announcement and the regular announcements for passengers to keep behind the yellow line. Relatively few accidents are caused by overcrowding on the platforms, and staff monitor platforms and passageways at busy times preventing people entering the system if they become overcrowded.
Suicide
Most fatalities on the network are suicides. Most platforms at deep tube stations have pits beneath the track, originally constructed to aid drainage of water from the platforms, but they also help prevent death or serious injury when a passenger falls or jumps in front of a train and aid access to the casualty. These pits are officially called "anti-suicide pits", colloquially "suicide pits" or "dead man's trenches". A person jumping or falling in front of a train is sometimes referred to by staff as a "one under". London Underground has a specialist therapy unit to deal with drivers' post-traumatic stress resulting from someone jumping under their train. Several stations on the Jubilee line extension are fitted with platform edge doors, which prevent people from falling or jumping onto the tracks.
Terrorism
has been a major concern because the Underground's importance makes it a prime target for attacks. Many warnings and several attacks, some successful, have been made on the Underground, the most recent on 21 July 2005, although in that case only the detonators exploded. The most recent attack causing damage was on 15 September 2017, when a man detonated a homemade bomb on a District line train at Parsons Green station. The earliest attack on the London Underground was in 1885, when a bomb exploded on a Metropolitan line train at Euston Square station. The Provisional IRA carried out over ten separate attacks between 1939 and 1993. As a response to growing 'Mumbai-Style' terrorist attack threats, the British Transport Police has its own detachment of armed officers who will regularly patrol both the Underground's stations and its trains.
Various regulations aim to improve safety on the Tube. Smoking was allowed in certain carriages in trains until 9 July 1984. In the middle of 1987 smoking was banned for a six-month trial period in all parts of the Underground, and the ban was made permanent after the major King's Cross fire in November 1987. From 1 June 2008 an alcohol ban was introduced on all TfL services. This change in policy was made by Boris Johnson soon after he was elected Mayor of London in May 2008. He claimed that a public transport drinking ban would reduce crime.
Fire risk
Following the 1987 King's Cross fire as well as the permanent smoking ban on all London Underground premises, the programme of wooden escalator replacement was sped up, and stricter controls on the storage of materials were introduced.
Photography
Photography for personal use is permitted in public areas of the Underground, with the purchase of a Student/Non-professional permit, to show the photographs to the public, requires additional payment, but the use of tripods and other supports is forbidden as it poses a danger in the often cramped spaces and crowds found underground. Flash photography is also forbidden as it may distract drivers and disrupt fire-detection equipment. For the same reason bright auto-focus assist lights should be switched off or covered when photographing in the Underground.
Criticism
The Underground's staff safety regimen has drawn criticism. In January 2002 it was fined £225,000 for breaching safety standards for workers. In court, the judge reprimanded the company for "sacrificing safety" to keep trains running "at all costs." Workers had been instructed to work in the dark with the power rails live, even during rainstorms. Several workers had received electric shocks as a result.
