Ambulances containing vomit and faeces can now be used to transport patients to hospital, according to new London Ambulance Service guidelines.

The new “off the road” procedure have been introduced to make maximum use of the capital's hard pressed ambulances and ensure that lives are not jeopardised by delays in treating seriously ill patients.

Staff in soiled or dirty ambulances could be asked to attend life-threatening calls if there are no other nearby ambulances available.

The crew would be asked to render aid to a patient at the scene until a clean vehicle arrived to transport the patient.

If necessary the patient could be taken to hospital in the dirty vehicle if that was operationally necessary, but only after staff have weighed up the risk of infection against their duty to save lives.

Vehicles with faulty “significant” equipment like a defibrillator or oxygen, or even a trolley bed, will also be able to attend a major incident.

Although vehicles soiled with other body fluids can attend new incidents, blood-stained vehicles or staff with soiled essential uniform can not.

The guidelines have angered many paramedics. One, who did not want to be named, said it is putting staff and patients at risk. They said: “There are real issues surrounding staff and patient welfare. We shouldn’t have to work in these conditions. During the recent snow, we would have to go to a job without any blankets, and there could have been vomit in the vehicle - how would that look to a patient? Basically, we have to treat people even if the ambulance is covered in faeces or urine.”

A spokesman for the London Ambulance Service said: “Over the last couple of months we have experienced an unprecedented level of demand on our services, and this policy has been implemented to ensure that anyone in a potentially life-threatening condition calling 999 for an ambulance will receive emergency medical attention as soon as possible.

“This policy is specific to the Service but reflects accepted practice in other ambulance services.

“The part of the policy in question only relates to circumstances when ambulance staff themselves are safely able to assess and treat a patient in a life-threatening condition. However, if their vehicle is faulty or infected, it will not be used if there is any risk to the patient’s wellbeing.”