The injuries suffered by victims of the attacks were typical of explosions and will in some cases cause lifelong disability, doctors said. They include burns, smoke inhalation, fractures, head injuries and internal injuries caused by the sheer physical force of the blast.

Many of the less seriously injured complained of hearing loss caused by ear drums perforated by the force of the blast.

John Heyworth, a consultant in accident and emergency medicine and former president of the British Association for Emergency Medicine, said: "In the past 15 years, we have developed a very sophisticated system for dealing with the injured patient. All hospitals now operate a standardised approach which saves lives."

The system is based on checking the patient's airway is free, ensuring they are breathing and checking their circulation - the ABC of saving lives. They may be given oxygen, bleeding is stopped and fluids can be given intravenously.

"It is addressed in a very co-ordinated way. You have to have a system in place. Medical teams have been waiting for something like this attack to happen," Dr Heyworth said. Some injuries looked more dramatic than they were. Many people emerging from tube stations yesterday with ash around their mouths and faces turned out not to be so badly hurt once the ash was cleaned away.

But other injuries, such as burns and smoke inhalation, could be more serious. "A lot of people with burns will do well. But I am afraid with these sort of explosions people suffer deep and extensive burns and may have life-long problems with repeated skin grafts," he said.

Most of those with perforated eardrums would take some weeks to heal but in some the injury would cause lasting hearing loss. "It is distressing and may be serious but in the context of the other injuries it is relatively minor," Dr Heyworth said.

One of the most taxing tasks for the mobile medical teams which were dispatched to the site of the attacks was to distinguish those who could be saved from those who were past help, so manpower could be focused on saving the maximum number of lives.

Each team had a medical incident commander appointed to prioritise patients and maintain control of the situation at each location where casualty clearing stations were set up.