Here's the thing about Geiger counters:
Geiger counters are used to detect ionizing radiation, usually beta particles and gamma rays, but certain models can detect alpha
While Gamma and Beta are higher energy particles, it is the alpha emitters (isotopes of plutonium for example) that are really troubling. Most devices
will not even detect these and some particular radionuclides can only be found through extensive lab testing.
In order to get an accurate measurement of how much radiation you are exposed to in any given area, you would need be able to examine minutely each
and every square millimeter of exposed surface and countless cubic meters of air due to the random nature of the spread of the pollution.
Picture a stream of smoke off of the end of a cigarette and you have some idea of what we are dealing with here regarding the way these contaminants
The aersolized particulates are sub-micron sized and are respirable (that is they would pass through the membranes in your lungs and enter your
bloodstream) and depending on which particular isotope lodge in a different portion of your body.
Iodine seeks your thyroid gland, strontium is a bone seeker, and each of the other isotopes go to muscle or other organs. Luckily, the vast majority
of the airborne releases peaked after the explosions of R3 & R4, but the waterborne release still continue and are exceedingly difficult to
If another big aftershock hits (and remember, there still has not been a M8+ sized quake which is still in the cards) and if the SFP (spent fuel pool)
of R4 is spilled, then we are all in a much deeper pile of poo than we are presently in.
There is no way to avoid what is in the environment at this point, the best you can do is limit your exposure and hope for the best.