Cell phones to detect radiation

Ephraim Fischbach and Jere Jenkins, the two Purdue researchers developing the system, say that these sensors could be the ideal way to detect and prevent terrorist acts using radioactive materials. Fischbach said in a statement, “It's the ubiquitous nature of cell phones and other portable electronic devices that give this system its power. It's meant to be small, cheap and eventually built into laptops, personal digital assistants and cell phones."

The researchers tested the system in November and were able to demonstrate that the solid-state sensors were able to detect a weak radiation source from 15 feet away. Jenkins said, “We set up a test source on campus, and people randomly walked around carrying these detectors. The test was extremely safe because we used a very weak, sealed radiation source, and we went through all of the necessary approval processes required for radiological safety. This was a source much weaker than you would see with a radiological dirty bomb."

The effectiveness of this type of detection system is compounded by the fact that one device alone isn’t responsible for locating the radioactive substance. Rather one device would detect the radioactivity and as the source of the radiation moved away from the device it would be picked up by additional devices allowing authorities to know in which direction the radioactive substance was moving.