Ionactive interactive

Ionactive is pleased to introduce the latest radiation protection widget resource produced for us by Dr Chris Robbins of Grallator. It is a companion to the Counting statistics (Radioactivity) Widget released late 2025. This widget asks the question 'Is the mean activity of an area of land above a given threshold?' This widget is highly interactive with many variables to alter and can demonstrate how you might answer questions such as : How big a survey sample size is required to be reasonably sure the mean site activity is below a desired threshold? Where should the measurements that make up the sample be taken? The widget is accompanied by a detailed paper written by Chris which explains the statistics and how they can be demonstrated by using the widget. 

Dose rate from a radioactive planar source calculator by Ionactive. This calculator will provide the dose rate from a planar radioactive source where the radioactivity is specified per unit area. The calculation point is by default at a perpendicular distance from the midpoint of the area source, but can be offset by any amount to investigate geometry effects. The planar source can be specified by the diameter of a circle or by entering x and y dimensions for a rectangular area. Output is provided as absorbed dose rate in air and effective dose rate at the point of interest. Comparison to a point source (of the same total activity) is also presented. A reverse calculation can also be made to provide the likely activity per unit area from a stated dose rate. This calculator can handle SI and non-SI units for both inputs and outputs. Shielding investigations can also be undertaken for lead, stee, concrete and water. This resource is mostly for education purposes in radiation protection and can be used together with the Ionactive point and line source calculators. 

Dose rate from a radioactive line source calculator by Ionactive. This calculator will provide the dose rate from a linear (line) radioactive source where the radioactivity is specified per unit length. The calculation point is by default at a perpendicular distance from the midpoint of the source, but can be offset by any amount to investigate geometry effects. Output is provided as absorbed dose rate in air and effective dose rate at the point of interest. Comparison to a point source (of the same total activity) is also presented, together with a geometry term indicating the angle (in radians) subtended by the active length of the radioactive line source at the calculation point. A reverse calculation can also be made to provide the likely activity per unit length from a stated dose rate. This calculator can handle SI and non-SI units for both inputs and outputs. This resource is mostly for education purposes in radiation protection and could be advertised as 'The calculator you’ll probably never need — and that’s the point' - you will need to have a play to discover why! 

An Ionactive neutron source dose rate calculator. With this calculator you can estimate the gamma and neutron dose rate from a radioactive source including AmBe, AmBe, Cf-252, PuBe, RaBe and more. Or try a reverse calculation and predict the activity of the source from the gamma, neutron or combined dose rates. Very much a 'what if' type calculator to provide an indication of likely external radiological hazard, particularly from legacy sources which could become unshielded. 

Ionactive has the pleasure of introducing the latest radiation protection widget resource produced for us by Dr Chris Robbins of Grallator. Take a journey into the concept of the Poisson distribution and how statistics (e.g. standard deviation etc) can be used when considering monitoring of radioactivity. The Counting statistics (Radioactivity) Widget (a simulator) can be used to investigate many counting attributes including false positive or false negative situations. For this widget we especially encourage our visitors to read the included paper by Chris and follow through with the examples given. A great learning resource, freely available to all.  

A specific activity calculator from Ionactive. Specific activity is a fundamental concept in radiation protection, nuclear medicine, radioactive materials handling and radioactive waste management. It explains why activity alone does not describe radiological significance, and why both the physical quantity of material and nuclear properties must be considered together. The specific activity of a radionuclide depends only on its half-life and molar mass. Materials with very long half-lives (such as U-238) therefore have low specific activities, even when present in large quantities. This calculator allows the user to enter data manually by providing the half-life and molar mass (which in most cases can be approximated to mass number if the raw radioactive material is being considered).  Or, the user can choose from a range of presents which provide exact half-life and molar mass data, and output specific activity, The user may also choose mass and activity conversion options.  The calculator offers  SI or non-SI unit options,  with or without scientific notation.