Victoreen Health Physics Slide Rule (ca. 1980)

The Health Physics Slide Rule was distributed by the Victoreen Instrument Company of Cleveland Ohio. Since the instruction booklet is identified as Rev. 3/79, I assume that the slide rule dates from sometime around 1980 or so. Quoting the instructions: "The VICTOREEN Health Physics Slide Rule has been designed to assist the health physicist, radiation protection officer, industrial hygienist, etc., in their protective endeavors."

The slide rule had several functions:  Given the activity of a specific radionuclide (Na-24, Co-60, Ra-226, Cs-137, Au-198, I-131, K-42, Xe-133, or Kr-85), the slide rule will calculate the exposure rate (mR/hr) at any distance.  Given a specific exposure rate (mR/hr) and an allowable exposure (mR), it will calculate the length of time that an individual can remain in the area. Given an elapsed time and the half-life of the source, the slide rule will determine the percent of the original activity that remains. If shielding is to be used to reduce a specified existing exposure rate to a lower exposure rate, the slide rule will calculate the required thickness of the shielding material (Pb, FE, Al, concrete, water) for different gamma ray energies. Finally, the slide rule will calculate the half life of a source given two measurements performed over a specified time interval. 

Size: 2" x 7"

Donated by Myron Fair.

Reference

Victoreen. Instruction booklet for Victoreen Health Physics Slide rule. Form 1083A Rev. 3/79.