I have not posted in a while, my apologies, it has been a busy week for me and my primary occupation has taken up a majority of my time.
However, it has been an interesting week to say the least. To start we had the neighborhood garage sale in our subdivision last Saturday, and it was a good time to go to garage sales. I woke up early on saturday and began a trek around our neighborhood and was able to score two radioactive items.
The first was a Westclock Baby Ben alarm clock, a nice vintage piece circa 1950's, early 1960's. It will trigger the alarm on my PM1703m, and measures around 650 counts per minute on my Digilert geiger counter. The second item is actually a really nice find, a Luminox Navy Seals wristwatch. The Navy Seal watch is actually standard issue, and the dial is illuminated by Tritium (Hydrogen 3, or H3) Traser glow tubes. Unfortunately I have not been able to detect any radiation from the watch, the mineral glass crystal shields most if not all the Xrays generated by the glass walls of the glow tubes. Hydrogen 3 is a beta emitter, when the glass walls and phosphors are struck by the beta particles, the generate Xrays in a phenomenon known as Xray fluorescence, or Bremsstrahlung. The X-Rays are very weak. Tritium is highly regulated in the United States, and the watch is one of the few unlicensed items able to be sold to US citizens. Other uses of the glow tubes are gun sights and bow sights.
On Wednesday I was at a Xxx's Xxxx at Penn and Memorial, and while shopping in the Pharmacy section my PM1703m alarmed. I detected somebody who had a Nuclear Medical test of some sort. Background at Xxx's Xxxx is quite low, 4 uR/hr. The maximum observed count was 60 uR/hr. This was a surprise since it has been many months since I have detected any radioactive people. I was not able to trace the source since the store was quite busy. There has been a shortage of Tc 99m, and it is less common for people to get tests done as a result.
I had mentioned in a precious blog that I had gotten some new scintillator probes, and thought I would test them out. After hooking up the largest one (a Bicron 2 1/2 inch scintillator probe) to my Ludlum Model 16 I went outdoors to test it out fully. What I was able to observe was a background rates of 100 Counts Per Second. My driveway was about 80 CPS, My Lawn 100 CPS, and finally near the down spouts of my gutters I measured 120 CPS. I am not sure what the source may be. It is from rainwater, and it could be from the plume from Fukushima Daiichi, or it could be from natural sources. There is no way to tell the origin without gamma spectroscopy equipment. By the way, the PM1703m measured higher rates on my lawn, however I was not able to tell the difference near the down spouts. The lawn is easy to explain, phosphate fertilizers and Nitrate fertilizers have a variety of Naturally Occurring Radioactive Isotopes such as K40, Uranium, and Thorium. The down spouts are not as easy to explain, since the I do not fertilize the roof of my house.
Overall, an eventful week. If anyone has questions feel free to post to the blog, or email. Hope you had a good week as well!
PM1703m 7 uR/hr; Not wearing the geiger counter watch.