The current random searches do only a minimum to improve security.

CNN: Screening must include religion, ethnicity

Catherine Farrell, of the Professional Association for Childcare and Early Years, said the government needed a "joined-up strategy" for childcare rather than the current "random set of proposals".

BBC: Childcare ratios: We will find way forward, says Cameron

But random erase is becoming more common, and is, for example, available in the current generation of Hewlett-Packard CD-RW drives.

CNN: Verbatim to ship first 4X CD-RW drive