Welcome to Harwell Dosimeters

Harwell Dosimeters Limited manufacture dosimeters for the radiation processing industry.

Two types - Red 4034 and Amber 3042 - are made from radiation-sensitive poly-methylmethacrylate (pmma) in the form of optically transparent pieces individually sealed in laminate sachets.

They darken when irradiated, and the radiation-induced darkening, accurately measurable by means of a spectrophotometer, is a function of the radiation dose absorbed.

The third type - Harwell Radspin - are pellets made of the amino acid alanine in a wax matrix. They are available as plain pellets, or individually sealed in aluminium blisters.

On irradiation a stable radical is produced, which enables delivered radiation dose to be measured using a paramagnetic resonance spectrometer.

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ASTM Dosimetry Workshop 2014

What's New

New Contact details for the new site

Dosimeter FAQs

We have a few questions that we get asked a lot, so we thought we would put together a list of the most common ones. If you would like us to answer any questions about our products, how they work, what they achieve then this is a good place to start