The US government's surviving nuclear fallout web page was updated on Friday

Right down the bottom of the page it says it was last updated on 25 February 2022.

I guess knowing about this page is a help. Here's a snippet:

• A nuclear explosion may occur with or without a few minutes warning.
• Fallout is most dangerous in the first few hours after the detonation when it is giving off the highest levels of radiation. It takes time for fallout to arrive back to ground level, often more than 15 minutes for areas outside of the immediate blast damage zones. This is enough time for you to be able to prevent significant radiation exposure by following these simple steps:

And here is the link.

From the weekend:

• The escalation of Russian sanctions and rhetoric doesn't bode well for Monday's market