Quickly,explain the circumstance you arrested him."
"Iep , Sergeant."

Arrested and being processed by the custody sergeant, this man that is accused of shoplifting will spend some time in the cells while officers decide what to do with him. But being isolated and alone to reflect on their temporary incarceration, make some prisoners vulnerable. Some tried to kill themselves or for other reasons lapse into unconsciousness.

Red alert! Red alert! Cell 29! Red alert! Red alert!

It's for this reason that here at a police station in Gwent, the cells are equipped with live scans(live scan是说可以即时扫描检测装置,如果说life scan则是说检测有无生命迹象的扫描装置,感觉好像到了外星才会用到,如果说囚犯没有了生命才检测到不是也没什么用处了? 感觉意思上live scan 合理些.) ---- devices that trigger an alarm when a prisoner is in need of emergency medical attention.

"What it is looking for is (the) lack of movement. Once it drops below a set level which is set by the company that installed this, we get an alarm that shows on here.Basically, the, the screen will turn red. The cell which is in alarm will superimpose itself into the center of the screen and will not shut off until we go in the cell and see what's wrong."

"These sensors are extremely difficult to fool. For instance if I just sat here very still and even held my breath the sensor(s) could even detect that my heart was beating."

The cells here at the station are also designed differently from traditional ones. For the most vulnerable, reinforced glass doors painted yellow are just supposed to have a calming effect. Other cells have a blue stripe, this according to forensic psychologists, affects a prisoner's brain and makes him tell the truth. Here they even have special cells for the severely intoxicated. Having no hatch means that custody staff have to physically go into the cell/ to check to see if they are alright. All this attention/ on the confidant safety of prisoners may appear a little excessive, but say the police, prisoners stand a better chance of reaching court in good shape to face justice.

Derryl Turner, Sky News.