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Geiger Counter Readings Juneau Flats

Readings of ionizing radiation are posted at G620Uranus Standard Geiger Counts per Minute Juneau Flats (gmcmap.com/historyData.asp?Param_ID=90604395640) every three hours.

Do not confuse this with cellular, microwave, or radio radiation. Microwaves can cook your food but won't even register. Geiger counters only detect ionizing radiation, which is far more dangerous. Even minute amounts can give you cancer.

That said, there's very little value in these periodic readings of background radiation in an interior room of my house. For example, it's extremely unlikely it would give any indication if the area was contaminated with radioactive dust. You need only look to post-Fukushima Japan. The nuclear reactor meltdowns showered Japan with radioactive microparticles. Background radiation may be normal. But hot spots were found in vacuum cleaner bags and automobile air filters as far away as Tokyo (). Bass, Thomas A. 2021. Fukushima today. Bulletin of the Atomic Scientists, Mar. 10. (Fukushima Today at archive.org.)

Background levels might have value for a science project. For example, does it fluctuate with the tides? But in the remote event of any actual outdoor contamination, it would probably just cover up the risk.

You should also note that the readings are only uncorrected counts per minute (CPM), can't be directly compared to readings from other Geiger counters, can't be used to infer radon exposure, and can't even be used to quantify danger.

You truly can't measure at a distance

An example is my Aladdin incandescent kerosene lamp mantle. From a foot away, there's no rise from background radiation. But a half-inch away, it registers 1,000 counts per minute. An unused spare mantle that hasn't had the coating burned off registers 1,500 counts per minute. Breathing the dust or a child ingesting it would be very, very not good.

Another example is my Grandfather's old self-winding Bulova watch (1953, date code L3 serial 5497642). I was thinking of having it cleaned and the Kreisler flex band fixed. From a foot away, there's nearly no rise from background radiation. But adjacent to the crystal, it reaches 3,600 counts per minute. It must have a radium dial. I thought the hands were dirty. On close examination, no, those are radiation burns. It doesn't even glow in the dark anymore. The radiation has broken down the phosphor. If I wore it, it would be adjacent to my wrist. Undetectable to a counter a foot away, but zapping the wrist 24/7/365. Maybe that's not a great idea.

If I want to get rid of it, the Alaska DEC indicates that it's perfectly legal to dispose of it in household trash (). Alaska DEC. 2020. Radiological Waste. Solid Waste Program, July 21. (Radiological Waste at Archive.org.) Somehow, that doesn't seem quite right. Maybe I'll just keep it so I can periodically verify that my Geiger counter is still working.


You may have such treasures in your home (). EPA. 2021. Radioactivity in Antiques. RadTown, Jun. 2. (Radioactivity in Antiques at Archive.org.) The only way you're going to find out is to get your very own Geiger Counter and sweep everything you've got. Mine is a GQElectronics.com GMC-500+, which has an M4011 standard tube. By default, it sends data about every two minutes. I changed it to every three hours to reduce Internet traffic. The device currently runs about $160 delivered. That's a bit expensive for something you didn't know you didn't need. But without it, I might have had that watch fixed, or worse, let a grand nephew disassemble it for fun. So it has paid for itself.

If you're worried about radon, a Geiger counter is the wrong tool. You can buy a Radon Guard model HRDM-01 battery-operated continuous reading digital detector for about $90 delivered. Mine claims about 1.33 long-term, 1.15 one-week, and 0.98 one-day average (pCi/L). Those are very low levels. Oddly, it reads higher if the window is open. Is it accurate? It's reasonably consistent with three mail-in tests I've used since about 1985. But the measurement in my house doesn't tell you anything about yours. Results can be drastically different just next door. You must get your own.

So there you are. I'm putting the continuing count on the web because I can, but I can't think of any obvious way it could ever be useful.

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