How Radioactive Is It? - A Summary Chart

Nuclear Radiation

How Radioactive Is It?
Common Radioactive Items Compared

Here is a chart of radioactive things that I have found. Each item was measured by 4 different Geiger Counters.

All radioactive sources were tested, using Ludlum, Eberline, Bicron, and Civil Defense Geiger Counters. In each case, the CPM (Counts per Minute) of each sample were recorded. The purpose of this summary, is to show the relative radioactivity of common items, which may be purchased at stores, flea markets, garage sales, and eBay.

. How Radioactive Is It? - Radioactive Sources From Least Radioactive to Most Radioactive .
-		Geiger Counter Manuf. =			Ludlum	Ludlum	Ludlum	Eberline	Bicron	Old CD
		Geiger Counter # =			Model 19	Model 3	Model 3	Custom	Model 50	CDV-700
		Sensitivity =			Lo energy Gamma	Alpha	Highest	Next	Less	Least
		Detector type =			1"x1" NaI scintillator	43-65 ZnS scintillator	pancake Geiger tube	pancake Geiger tube	end window Geiger tube	side window Geiger tube
#	Radioactive Item Description	Radioactive Item	Size	Isotope	Ludlum µREM	Ludlum Count	Ludlum Count	Eberline Count	Bicron 50 Count	. CDV-700 Count
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	-	Background	atomic	random	10	5	50	30	25	20
1	from Arizona	#2 weak Uraninite	>1"	Uranium-238	10	5	60	30	30	20
2	from Arizona	#1 weak Uraninite	>1"	Uranium-238	20	5	100	60	60	20
3	2% Thorium	Welding rod, red tip	1/8 x 7"	Thorium-228	10	30	300	250	40	30
4	Uranium Glass	3 glass marbles	1/2"	Uranium-238	10	5	450	250	100	40
-	Depression glass	Dessert plate	8 3/8"	Uranium-238	15	40	1,200	600	130	80
5	from Arizona	#3 uranium ore	>1"	Uranium-238	20	50	2,400	1,000	450	200
6	from N. Carolina	Megalodon tooth	5"	Uranium-238	40	120	2,600	1,200	320	200
7	from Wyoming	Schrockingerite	1"	Uranium-238	15	no measure	3,200	1,600	600	500
8	CDV-700 Meter	700 check source	1/4"	Cesium-137-?	10	5	5,000	2,600	1,800	1,800
9	from Arizona	Uraninite/ carnotite	5"	Uranium-238	50	600	8,000	4,000	1,000	800
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10	contain thorium	Lantern mantles (10)	2" x 3"	Thorium-228	180	no measure	21,000	7,000	2,000	1,300
11	from Spokane, WA	Autunite crystals in bag	1/2"	Uranium-238	60	no measure	22,000	20,000	3,500	2,800
12	Fiestaware (red)	Coffee Cup	3"	Uranium-238	25	700	32,000	14,000	3,200	3,000
13	Fiestaware (red)	Saucer - 6"	6"	Uranium-238	32	6.000	32,000	14,000	3,000	3,000
14	Fiestaware (red)	Saucer - 6"	6"	Uranium-238	32	6.000	32,000	14,000	3,000	3,000
15	Parma (red)	Salad Plate - 8"	8"	Uranium-238	34	2,400	34,000	12,000	3,000	2,000
16	Fiestaware (red)	Bowl	6 3/4"	Uranium-238	46	2,000	40,000	16,000	4,000	5,000
17	Metlox (red)	Salad Plate - 7 1/2"	7 1/2"	Uranium-238	42	2,600	40,000	14,000	3,400	2,800
18	Padre (red)	Salad Plate - 7 1/2"	7 1/2"	Uranium-238	44	3.200	42,000	16,000	3,800	3,200
19	Fiestaware (red)	Serving plate	14 1/4"	Uranium-238	80	3,200	43,000	18,000	4,500	4,000
20	from Spokane, WA	Autunite cluster	1/2"	Uranium-238	45	no measure	46,000	22,000	10,000	8,000
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21	Smoke detector	Detector sensor	1/8"	Americium-241	160	100,000	80,000	42,000	14,000	250
22	from Colorado	Coffinite - 5"	5"	Uranium-238	800	9.000	110,000	32,000	10,000	8,000
23	from Colorado	Uraninite - 7"	7"	Uranium-238	1,200	13,000	150,000	44,000	15,000	12,000
24	from Shinkolabwe	Gummite	1/2"	Uranium-238	600	no measure	220,000	58,000	60,000	180,000
25	from Congo	Torbernite	1"	Uranium-238	900	12,000	330,000	> 60,000	50,000	28,000
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NOTES:		1. Seemingly anomalous readings are shown in red text. 2. Response curves are not linear, and vary for several reasons - radiation type, detector response, distance from detector surface caused by sample size and shape, detector size and shape, etc. 3. Millions of people have been eating off of "Radioactive Red" Fiestaware for many decades. This gives me the willies. 4. "No measure" applies to samples stored in plastic bags which block alpha particles. I choose not to remove the samples, due to their crumbling, flaking, disintegrating nature. 5. With the Ludlum Model 19, I measured one item with the case removed = 500 µREM. The same sample when measured with the case in place resulted in = 400 µREM. So, you can figure on a 20% reduction in incoming energy using the case as intended. 6. The Ludlum Model 19 shows an average background of about 9µ REM. When it was 12µREM, I discovered some samples about 5 feet away - not good enough. I use a 20ft no-sample zone now. I still can't figure out where those extra few µREM are coming from. .
NOTES:		Items which I will be adding over time (with guess at energy level) - * Brazil nuts (radium) (no gamma on Model #19) * Kitty litter (bentonite) * Magazine cover (kaolin clay) * Water-softener salt (potassium chloride) Fertilizer (high phosphate) *** Uranium-glazed Cloisonné jewelry (yellow) *** Radium alarm clock dial (painted hands and numbers) ****** Depleted uranium penetrators (bullets) Anything else I can find that is "hot" If you have something hotter than my Torbernite above, and want to sell it, send me an email. If you have a depleted uranium penetrator, rent it to me for 1 day for $30, and I will return it to you. .
50	170	160-895	60	100	75	75	75	75	75	75

. Uranium Isotope Concentrations Natural vs. Enriched Uranium
	. Enriched Uranium			Natural Uranium %	Depleted Uranium %
	Weapons Grade Uranium %	Highly-Enriched Weapons-Usable Grade Uranium %	Enriched Reactor Grade Uranium %	Natural Uranium %	Depleted Uranium %
U-234	-	-	-	0.0055	0.0009
U-235	90.0	20.0	4.0	0.71	0.20
U-238	10.0	80.0	96.0	99.28	99.80
REM	Highest	Higher	High	Medium	Medium
75	125-650	125	125	100	100

DISCLAIMER
I am building this page for self-education.
Although the author has tried to be as accurate as possible, errors are possible.

I could not find a Summary Chart of radioactive substances quite like the above. So, I made this ionizing radiation measurement summary chart, to help myself understand radioactivity. I hope that it helps you.

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This Vaughns How-Radioactive-Is-It? Summary Chart web page was updated on 2011-04-28.