Here you go, a primary source: https://radiationserviceswa.com.au/missing-radioactive-source-in-western-australia/ https://radiationserviceswa.com.au/missing-ra

Here you go, a primary source: https://radiationserviceswa.com.au/missing-radioactive-source-in-western-australia/ https://radiationserviceswa.com.au/missing-radioactive-sourc... excerpt>>> The risk with radiation sources dramatically increases within 1 m – we can calculate the dose rate using the ‘inverse square law’: At 1 cm, the dose rate will be 10,000 time higher …. 16,650 mSv/h (or 16.65 Sv/h) At 1mm (ie, if you were to pick the source up with your fingers), the dose rate would be 1,665 Sv/h – this will cause some serious damage to your fingers and surrounding tissues. >>> I'm a little suspicious of their inverse-square calculation, though, as by their logic the dose rate would be infinite at a distance of 0m (skin contact). That's clearly not the case.