[quote=ucodegen][quote=Eugene]Rad is not a unit of fallout. That map is meaningless.[/quote]
But Rad is a measurement of ionizing (high energy) radiation, which is related to fallout. It indicates the strength if its related to units of time.
You use rads to measure the cumulative amount of radiation, or ‘the dose’, absorbed by your body. At any given level of fallout, your dose depends on the duration of exposure, being indoors/outdoors, having an air filter in your AC that traps radioactive particles, etc. etc.
At the very least, they would want to use rads per hour. (And I’m pretty sure that the map does not show rads per hour. 750 rads/hr is the level of radiation 20 miles downwind of a 1 megaton nuclear explosion, not something you see 5000 miles from a reactor meltdown.)
The correct unit to measure fallout is becquerels per square meter or curies per square kilometer.
