Hi Lucinda. I'm sorry to hear about your friends and their family. I will keep them in thoughts and prayers.

As for Radon and quakes, take a look here:
http://www.ciw.edu/CIW-news-earthquake.html
http://sedwww.cr.usgs.gov:8080/radon/radonhome.html
http://www.epa.gov/iaq/radon/
http://radon.com/

There are a number of others out there - I used Hotbot search engine: http://www.hotbot.com and entered 'earthquake radon' for the search.

Canie