Uranium decays to radium which decays to radon, a gas. The real danger to uranium ore is inhaling radon. Also, the staff should be much more concerned than any tourist. The tourist angle seems sensationalistic, and a lost opportunity for informing the public about the dangers of radon.

unitednuclear.com sells uranium ore in addition to more exciting radioactive elements, and they have (had?) a page somewhere describing the need for good ventilation anywhere you store more than a small sample of ore.

EDIT: Maybe I was thinking of the product page for their radon gas detector, http://unitednuclear.com/index.php?main_page=product_info&pr...

  We purchased one of these detectors for ourselves and put in
  in the room where we stored our Uranium ore samples. The
  device indicated over 100 pCi/L ! For reference, the average
  indoor reading is 2pCi/L... at a reading of 100 pCi/L,
  immediate evacuation is called for.

  ...

  Since we do sell Uranium ore samples, it's important that we
  stress a point. Collecting and storing a few Uranium ore
  samples is not going to create dangerous levels of Radon gas
  in your home. However, if you are and avid collector, and
  you have several pounds of Uranium ore in your home, you'd
  should consider buying one.

Interesting, thank you. I didn't know radon was created that quickly.

The article mentions that the ore was discovered by chance by a young man with a geiger counter. Maybe it was the actually the radon he detected?

The decay chain to radon is slow, but the ore itself already has plenty of the intermediate products, including significant amounts of the immediate precursor radium, as its been sitting around for billions of years. AFAIU most of the measurable radiation from uranium ore comes from radium decay, so, yes, I assume what he was detecting was the decay chain starting from radium to radon.

The half-life of radon is very short (a few days), but that's part of what makes it so dangerous, along with being a gas and the fact that radon decay is itself highly energetic regardless of the half-life.

You can see the decay chain here: https://en.wikipedia.org/wiki/Uranium-238#Radium_series_(or_... The whole radon decay chain (radon->polonium->lead) happens quickly and is the most energetic part of the uranium decay chain. And because you can easily inhale radon, it can all occur inside your lungs where even alpha particles (especially alpha particles, actually) can damage cells. Basically, a lot of energy released in a very short amount of time within unprotected tissue. So while uranium ore may emit only a tiny amount of radon, radon itself is nasty enough that you can inadvertently go from harmless to potentially harmful by storing more than a handful of uranium ore in a confined space.

I'm not doing the actual science justice and perhaps mincing terminology (not my field), but that decay table should speak for itself.