As workers at the wrecked Fukushima reactor learned, there is no equipment available that can accurately measure all three types of radiation (alpha, beta and gamma) at the same time. Having separate detectors for each is not only cumbersome and expensive, it also forces workers to spend more time in the contaminated area, increasing exposure. Researchers in Japan have developed a hybrid detector with three different “scintillator” layers. The first, made of plastic, emits a pulse of light when struck by alpha particles; the second does the same for beta particles; the third detects gamma rays. The instrument examines the signals separately and calculates the dose of each. – Alex Hutchinson
Alpha
Particle effects: Most cannot penetrate human skin, but are harmful if swallowed or inhaled.
Detected by: Plastic
Beta
Particle effects: Can penetrate to where human skin cells are produced.
Detected by: Gadolinium silicon oxide
Gamma
Particle effects: Able to burrow centimetres into human tissue.
Detected by: Gadolinium silicon oxide
