According to tests conducted by physicists at the Australian Nuclear Science and Technology Organization, the smartphone app Radioactivity Counter really works. Results from the tests conducted by ANSTO showed that the two tested phones using the app were “sensitive enough to detect radiation at levels which are significant in a radiological event.”
Radioactivity Counter claims to measure individual exposure to radiation. The app supposedly can accurately detect a dose of radiation (using the radiation unit microGray per hour) using the camera in a smartphone, which is sensitive to both visible and high energy gamma photons.
The app takes advantage of the radiation sensitivity of the built-in silicon-based complementary metal-oxide-semiconductor cameras to monitor ambient radiation levels.
Details on ANSTO tests
Alison Flynn and several ANSTO colleagues decided to run tests to verify Radioactivity Counter’s claims using two smartphones: the Apple iPhone 4S and the Samsung Galaxy S2.
The devices were tested at ANSTO’s Instrument Calibration Facility, and the results showed the app can accurately measure exposure to radiation.
Radioactivity Counter: Test results
The overall result was that the app enabled both smartphones to produce a linear response to changes in dose of radiation, which means if accurately calibrated, the phone can to reliably determine the potential dose rate to which a person is being exposed.
Both phones demonstrated counts per minute that were directly proportional to the dose rate for dose rates above 20 MicroGy/h for the Samsung and 30 MicroGy/h for the iPhone (Fig. 2). The average radiation dose rate on a long haul airline flight is typically close to 7 MicroGy/h.
The somewhat poorer performance of the iPhone is likely because only the front camera could be used; meaning there was a chance light from the screen could be detected inside the camera through the top layer of glass.
Moreover, the angular response of the phones from 0° to 180° for a dose rate of 50 MicroSv/h and 150 MicroSv/h is displayed graphically in Figs. and 4. These results demonstrate that both phones have a response independent of the orientation of the phone. This means they are well suited for use as radiation detection devices as the detecting function is unimpaired even if the phone is carried in a pocket, purse or backpack.