Radiation Hazard in Western Australia: What Is Known

Authorities have declared a radiation hazard in part of Western Australia due to an 8 mm by 6 mm radioactive capsule – 19-GBq  caesium-137 ceramic source, which fell out of a truck. The capsule is part of a gauge used at the Gudai-Darri mine to measure the density of the iron ore feed and transported to the depot by a truck with radioactive materials.

It is known that on 12 January, a truck with a capsule left a mine in the Pilbara region of Western Australia and went to a warehouse in the capital of Perth, where it arrived on 16 January. In 9 days, on 25 January, when the gauge was unpacked for inspection, it was found broken apart, with one of four mounting bolts missing and screws from the gauge also gone. Authorities suspect vibrations from the truck caused the screws and the bolt to come loose, and the radioactive capsule from the gauge fell out of the package and then out of a gap in the truck.

The total distance a truck traveled from the mine to Perth is approximately 1400 km.  The Western Australian Department of Fire and Emergency Services has already deployed search groups with radiation detection devices and metal detectors in critical sections of the truck’s route, particularly in densely populated areas. In addition, the authorities will provide cars in the region with new radiation detection equipment.

The leadership of the Western Australian rescue service acknowledged that the capsule with highly radioactive material may never be found.

Health authorities have warned the public about the hazard and urged not to take the capsule in hand and not to approach it if it is seen. Standing at one meter’s distance from the missing capsule is similar to receiving 10 X-rays per hour.

The radioactive material in the capsule, which emits both gamma and beta rays, has a half-life of 30 years. Close exposure can result in burns, longer exposure can cause acute radiation sickness, and there is a long-term risk of cancer.

According to the Guardian