RadCalcLE™ is a utility program to aid people using Ludlum instruments in determining certain detection limits quickly, easily, and accurately. "LE" stands for "Ludlum Edition." RadCalcLE version 1.0 performs all of the important statistical calculations for radioactive surface contamination measurements including minimum detectable activity (MDA), detection limit (sometimes called minimum detectable count rate or MDCR), and critical level (Lc). It also calculates sample activity. Input and results can be in any commonly used U.S. or metric units of count rate, activity, and area — all unit conversions are performed automatically. Specific Ludlum instruments and detectors can be selected from dropdown lists so that it is not necessary to calculate time constants or detector area. These parameters can also be input manually if you wish to use this software with instruments or detectors from other manufacturers.

This program is designed be intuitive and extremely simple to use. Results can be printed for reference, saved as a text file (for import into word processing programs), or copied and pasted into other applications. RadCalcLE continuously updates the results given, so no "calculate" button needs to be pressed and no bogus results will ever be displayed, saved, or printed.

RadCalcLE is free to use and distribute (so long as you don't charge for it!). The full version, RadCalc Pro, is available from RadPro. RadCalc Pro additionally calculates detection limits for wipe and air samples; calculates radioactive decay and half life; contains a large database of radioactive isotopes including radiations, energies, and intensities; performs many unit conversions; and more. RadCalc Pro can be downloaded from RadPro's website.

Download the RadCalcLE utility program

You will be given the option to "Save to Disk" or "Open" the program after completing the above procedure. Select "Save to Disk". Unzip the files and double-click on RadCalcLE.exe to run the program.