I have a radiation survey meter that I bought 25 years ago at a garage sale for $5.
Last year I sent it to www.KI4U.com to have it repaired and calibrated.
Took it to the grocery store.
Veggies and fruit = no reading.
Shelves of canned tuna = .05 rads/hr.
What does that mean?
I am not an alarmist about background radiation. However, I am concerned when extreme Greens rejoice in the “death lottery” and the reduction of human population via Fukushima.
What does that mean?
It may mean that the tuna grew up closer to a natural source of radiation, nearer the center of earth itself.
“Shelves of canned tuna = .05 rads/hr. What does that mean?”
Not much. 1 rad = 1 rem. Your reading is 5/100ths of a rad every hour and that isn’t much to be worried about.
In a high altitude city like Denver, a person would have 80 rem a year in exposure just from background radiation alone.
Frankly, I would be more concerned with the amount of mercury in canned tuna. Since I only like fresh tuna and that infrequently, the canned stuff is stored for emergencies.