Radiation protection widgets & calculators

This criticality widget presents a hands on interactive educational aid for understanding criticality in nuclear materials. The widget provides three sections; the first demonstrates neutron population in sub-critical, critical and supercritical systems for two different geometries. The same section also demonstrates the use of a reflector and how this can reduce the effective critical mass of the system for critical and supercritical conditions. The second section considers the approach of two subcritical fissile objects  - reaching critical and supercritical conditions. The final section considers delayed neutrons and how they can significantly alter the power build up (or drop) timescales over orders of magnitude from 10's of micro seconds to 100's of seconds (i.e uncontrollable vs controllable). This resource has been created for Ionactive by Dr Chris Robbins of Grallator

A nice and simple visual and interactive way of understanding the inverse square law as applied to radiation protection. 

Imagine a radioactive source holder breaking away from an industrial nuclear gauge  - forming a small aperture from which gamma rays can be emitted. What would the dose rate be at various distances from the aperture, and what % of the body trunk would be exposed at each distance? When would an equivalent dose to a part of the body become a whole body effective dose? This interactive widget sets out to answer these questions. 

This resource uses a radiation protection widget to explore the validity of a popular gamma dose rate formula of the form:

\[ \begin{align} D_{\mu Sv hr^{-1}} &= \frac{AE}{6 r^2 } \end{align} \]

where D is dose rate in µSv/h, A is activity in (MBq), E is gamma ray energy in MeV, and r is the distance in m.

Large volumes of water (in pools / ponds) are often used for radiation shielding, particularly for spent nuclear fuel and high activity Co-60 sources in industrial irradiation facilities. The water provides shielding and cooling whilst allowing remote movement of highly radioactive items where operators stand safely outside the pool. Imagine falling in - how would you fair? Very well if you can swim as illustrated in this radiation protection widget.

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.