Beckman Scientific Instruments Division~item 63~radioactive decay table ruler~H3 for Sale

Beckman Scientific Instruments Division~item 63~radioactive decay table ruler~H3 For Sale

Beckman Scientific Instruments Division~item 63~radioactive decay table ruler~H3:
$4.99

For sale is a vintage Beckman Scientific Instruments Division item. It appears to be a plastic ruler, but it is not and has charts with Decay tables for Chromium 51, Cobalt 60, Iron 59, Phosphorus 32, Iodine 125, Sulphur 35, Tritium and Iodine 131. The other side has an "Accuracy Statistical Scale for 95% Level of Confidence" and a "Decay Scale for Radioactive Isotopes" which correlates the number of half lives with the % activity remaining. There is no indication of date, just that it is "item 63" and the number S741251-474-5CP. I seems like the sort of thing that might have been scientific meeting swag or perhaps a freebie with a big order. It is 11.5" long and 1.75" wide. It is in very good condition, with just some ink smudges from sitting in drawer for years.....