New research by scientists have found that the subscriber identity module (SIM) card can survive heat up to 450°C and possibly beyond, which could help probes into terror attacks and other crimes. The SIM card is the heart of a mobile phone, as it provide a record of numbers received, dialled and also text messaged.
In an unusual investigation, electronic engineers Benjamin Jones and Tony Kenyon, both from University College London, subjected the SIM cards by burning them. Collecting 12 cards, all recently or currently in use, from members of the public in Britain, Ireland and Sweden.
Using acid, it removed the protective epoxy moulding surrounding the chip to expose the circuitry. Then the cards were placed in heated air for 10 minutes, then were allowed to cool down. The researchers then sought to recover the data by attaching tiny probes to the circuit and reading the contents via an interface pad.
Six were heated to around 180°C and could be read after rewiring with no loss of data
Five were cooked to 450°C, with four could not be read and one could, briefly.
One was cooked to 650°C and could not be read.
They also pointed out that the rewiring technique used is not the last resort for forensic experts, with other hi-tech data-reading methods could be used.
In addition, SIM cards survive much longer in a blaze if they were close to the floor or on a desk.
Their paper appears in the latest issue of Forensic Science International journal.