Technical Guidance

Use this interactive ALARP / ALARA calculator widget to investigate the effect of time, distance and shielding on radiation dose rate and accumulated exposure. A great radiation protection training / educational aid - learn the concepts first, then investigate them interactively! Explore how best to optimise exposure by using a combination of all three protection methods. Version 2 (released February 2026) now includes custom inputs - use this widget as an ALARP calculator in your own projects. 

A radiation protection widget which calculates dose rates from an x-ray tube for a given kV, mA and filter (Al). This resource is strictly for training / educational use - that said, as a ballpark resource it gets pretty close to what you might expect from a typical x-ray tube.

How do you calculate an estimate of dose rate from an X-ray tube give kV and mA? In this resource we consider a 'ballpark' estimate of radiation dose rate using some physics principles, including an estimate of % bremsstrahlung from an anode target, combined with a calculation of power density and consideration of average energy absorption rate.

When \( 1/d^2 \) breaks down - part 2: area source. Using some mathematics to explore how the inverse square law works with a radiation area source.

When \( 1/d^2 \) breaks down - part 1: line source. Using some mathematics to explore how the inverse square law works with a radiation line source.

At Ionactive we are often asked 'What is a Radiation Protection Adviser (RPA), and do we need one?' This is an interesting question and concept, since the question is aimed directly at an RPA. We give objective advice and for most uses of ionising radiation a Radiation Protection Adviser is required, sometimes only for initial advice via consultation, but more often than not via an official appointment (in writing). Here is a quick summary of the role of the RPA and why a user of ionising radiation will probably need to appoint an RPA.