Tube heat reaches dangerous levels

Tube passengers were being exposed to dangerous levels of heat and humidity today.

As Britain stands on the brink of record- breaking temperatures expected to top the 37.1C (98.8F) record set in 1990, commuters on Underground trains and stations were suffering "inhuman" conditions.

Using state-of-the art air-quality testing devices to measure heat, apparent temperatures - combined heat and humidity - were found to reach 52C (126F).

The worst conditions yesterday were in a waiting room on the platform at Hammersmith station, with temperatures up to 38.4C (101F). With a relative humidity of 55 per cent the apparent temperature was 52C (126F). The legal maximum for transporting animals is 35C (95F).

On one crowded Circle line train at 5pm yesterday the temperature was 33.9C with a relative humidity of 65 per cent, creating an apparent temperature of 48C (119F).

The danger when heat and humidity combine is that it reduces the amount of evaporation of sweat, preventing the body from cooling itself effectively.

London Underground today announced that it has nine tons of bottled water in reserve to cool down passengers. It took the unprecedented step of ordering more than 15,000 half-litre bottles in case commuter trains break down and become stranded.

LU has been forced to take the measure because Tube trains do not have air-conditioning. Conditions underground could swiftly become serious on a packed train.

An LU spokeswoman said: "The forecast is for very high temperatures today and we want to be ready. A stranded train could have 1,000 people on board."

The spokeswoman emphasised the water would only be handed out in an emergency.

The National Oceanic and Atmospheric Administration -
America's version of the Met Office - classifies any temperature above 41C (105F) as dangerous, and any temperature above 54C (130F) as extremely dangerous and likely to cause heat stroke, which can kill.

Key recommendations for coping with the heat are to drink plenty of water to avoid dehydration. If people feel tired or have a headache, high pulse rate or shallow breathing, they should slow down and cool off.

Heat exhaustion is caused by the loss of fluid and salt through perspiration or replacing them in an imbalanced way. It can lead to dizziness and weakness. In some cases victims, especially the elderly, should be treated in hospital.

With heat stroke the body's thermostat can be severely upset, causing body temperature to rise to 41C (105F) or higher. Symptoms are lethargy, confusion and unconsciousness. Even a suspicion that someone might be suffering from heat stroke requires immediate medical aid.

Passengers on the Tube during yesterday's rush hour were not impressed with the conditions.

Fidelma O'Donnell, a 38-year-old accountant travelling home on the Victoria line said: "I'm not surprised that these temperatures make some people ill - it is like a cattle truck."

Paul Staples, a 37-year-old project manager travelling on the Northern line, said: "I hate the state that I get to work in - sweating like a pig."

On mainline railways it will be the third successive day of delays caused by hot weather. All trains operated by Connex, South Central and South West Trains will be limited to 60mph in case rails buckle in the heat.

In some places the speeds could come down to as low as 20mph. The restrictions will come into force at lunchtime and last until 8pm. Network Rail, responsible for the infrastructure, said at least two rails buckled in the heat yesterday, one near Gatwick and another in the Midlands.

But Chris Green, chief executive of Virgin Trains, said rail managers have overreacted. Last month's decision to charge six rail managers with manslaughter for the Hatfield crash had shaken Network Rail's confidence, he said.