4 ms·
The facts in this article are somewhat incongruous: Radiation levels due to nuclear testing were elevated 7% over normal The major source of radioactivity in
by cmsmith 13y ago
The facts in this article are somewhat incongruous:
Radiation levels due to nuclear testing were elevated 7% over normal
The major source of radioactivity in steel is cobalt 60, which has a half life of 5.27 years
In which case one could just wait a year and the radioactivity of your steel would drop by 7%, making up for the effects of nuclear testing contamination. Put another way, steel from 1944 has been around for some 10 half-lifes of cobalt-60, meaning it has 1/2^10th as much 60Co radiation as when it was made. Why would it matter if the radioactivity was 1/2^10th or 1.07/2^10th as much as the background radiation?
I'm sure there are other isotopes which make this more of a problem, but the facts as presented in this article don't make much sense.
- InclinedPlane 13y agoThat's why low background steel isn't as much in demand as it used to be. It helps that it's easier to make it from scratch by filtering the air better. Even so, there are still some rare cases where it's easier to use older steel to ensure that there is much lower background radiation. Co-60 isn't the only source of radiation, and even 1/1,000th of peak levels can still be fairly high for applications like neutrino detectors.