It uses some strange units - CPM, may be "Counts Per Minute", looks weird for me, because different radiation sensors have different CPM value per uSv/h or uR/h for different radiation sources. It heavily depends on the sensitivity and size of the geiger tube or scintillation sensor and used to calculate measured radiation level from number of particle detection pulses per minute. Looks like radiation level in CPM is something adjusted to CPM of some standard sesnsor.
Searched a little, some sources state that 1uSv/h is 120 CPM with Cs137 source standard, some state that it is 108 CPM with Co60 source standard.
So anything higher ~60 CPM (0.5uSv/h) should be cause of concern, anything higher than ~360CPM ( 3uSv/h like during plane flight) is a reason to move out.
Well in that case the triple and quadruple digit readings in the US should be a cause for concern.
https://www.gmcmap.com
It uses some strange units - CPM, may be "Counts Per Minute", looks weird for me, because different radiation sensors have different CPM value per uSv/h or uR/h for different radiation sources. It heavily depends on the sensitivity and size of the geiger tube or scintillation sensor and used to calculate measured radiation level from number of particle detection pulses per minute. Looks like radiation level in CPM is something adjusted to CPM of some standard sesnsor.
Searched a little, some sources state that 1uSv/h is 120 CPM with Cs137 source standard, some state that it is 108 CPM with Co60 source standard.
So anything higher ~60 CPM (0.5uSv/h) should be cause of concern, anything higher than ~360CPM ( 3uSv/h like during plane flight) is a reason to move out.