In uncertainty following the Fukushima Daiichi incident, citizen science groups Safecast and Radiation Watch have been providing a critical service for nervous residents, both by building radiation monitors and collecting data from the fallout zone. IEEE Spectrum reports.
Safecast was organized just days after the explosions. Its founders hoped to buy and distribute Geiger counters to residents in the fallout zone so they could do their own monitoring, but the world's supply of Geiger counters had already sold out.
So the tech-savvy, DIY-inclined volunteers built their own device that they called a bGeigie (pictured above), which they had strapped to their cars while they drove through Fukushima. The bGeigie takes a radiation reading every five seconds and tags it with the GPS location; that data is used to build the maps that Safecast puts online.
Their bGeigie devices (the “b” is for “bento”) costs $1000 per unit. Twenty-five have been deployed. At a school playground, for example, the device showed that decontamination work had been relatively effective in the playground itself, but radiation levels were higher in the undergrowth on the edges of the play area.
The group is now working with the country's postal agency, Japan Post. With bGeigies on deliverymen’s motorbikes, radiation data will be collected daily for the Safecast maps.
Meanwhile, Radiation Watch have been building radiation monitors that connect to smartphones -- called Pocket Geigers (pictured). They developed their first one in August 2011: a cheap PIN photodiode detector to sense radiation, and a smartphone app to pair the radiation data with GPS information. Its first open-source device sold for $23.
The latest model takes two minutes to get a dose-rate reading -- this fifth generation device costs about $70. There’re now about 12,000 Pocket Geiger users.