The Government is to consider installing electronic body scanners which can detect mobile phones and metal weapons hidden inside people’s bodies into every jail in England and Wales.

David Hanson, the Prisons Minister, said today that putting the £6,500 scanner in every jail would help to counter the growing number of mobile phones being smuggled into prisons.

Trials with the scanner have taken place on new arrivals and those arriving back at prison from court hearings in eight top security jails over the past year as part of the national drive to prevent phones, guns and knives being illicitly taken into prisons.

The body orifice security scanner (Boss) is a mobile chair with three sensitive sensors which can detect metal items as small as a pin or paper clip when they are hidden on or inside an individual.

A prisoner sits on the chair and the machine issues a red alert when an object is found within or around the body. Mobile phones are frequently smuggled into jails in body orifices.

“I would be really keen to look at how we can roll out the development of the Boss chair in other prisons," Mr Hanson said. "It is a valuable tool towards identifying mobile phones being brought into prisons.

“The mobile phone threat in prison is particularly difficult. We want to prevent mobile phones coming in, to prevent contact with drug runners on the outside, to prevent intimidation and to prevent indviudals running criminal activities from inside.

“Mobile phones can be used for drug activities in prisons and to contact the outside world including to intimidate witnesses.”

Mr Hanson said that the Boss chair offered a better way of dealing with mobile phones than trying to instal a jamming system as this would also effect the use of mobile phones in nearby houses and on roads in the vicinity.

Two Boss chairs are being used in Woodhill jail at Milton Keynes and have helped detect 21 mobile phones since April including one on Tuesday night. It is so sensitive that it can detect a concealed Sim card.

If an alert is issued when a prisoner sits in the chair, he is then given a second scan over his body with a hand held detector. If the prisoner denies he has any metal object on him, he is taken to the segregation unit and checked with the hand held metal detector on every occasion he leaves the cell.

Most prisoners quickly admit they have a mobile phone rather than undergo regular checks though the longest period an inmate at Woodhill has concealed a mobile within his body was four days.

If an inmate leaves his cell in the segregation unit and the handheld scanner fail to detect any metal, it alerts the prison to the fact that the inmate has taken it from his body and hidden it elsewhere in the cell.

Luke Serjeant, governor of Woodhill, said that he thought installing the Boss chair would be worthwhile as it could deter drug dealing. He said that a recent find of drugs at the jail had a value outside the prison of £5,000.

Overall up to 400 mobile phones a month have been seized in jails in Englands each month since October 2006.

Earlier this month it was disclosed that almost 250 mobile phones had been found inside Wandsworth jail in south west London in the first five months of the year.

Despite the enthusiasm of the staff and governor of Woodhill jail for the Boss chair, they recognise that prisoners with lots of time on their hands will always plot to defeat security systems.

Asked whether there are a lot of mobile phones in the jail, John 41, from Dunstable, serving 12 months for theft, replied: “What you need to realise is that prisoners are sitting here for 24 hours. They will think of things to get round searches. You have also got to remember that a lot of mobile phones are now plastic.”

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