Radioactivity services

Standard radionuclide solutions

NPL’s standardised radionuclide solutions are prepared over a range of activities, using a chemical composition that ensures stability for the radionuclide of interest. Most of our ampoules are supplied with a Certificate of Measurement accredited to ISO 17025 by UKAS. Many radionuclides are currently available from our stock. We can also produce custom radionuclides; please see the section below.

Stock Solutions

NPL offers standardised solutions which are dispensed from bulk stock solutions that have either been assayed using the techniques used for UK primary standards or been assayed using transfer instruments (previously calibrated using a primary standard).  

Standardised solutions from stock are supplied in flame sealed glass ampoules. Please also note NPL are currently developing a new range of stock standards of a number of radionuclides, including Pa-231, Zr-93, Po-209, Ac-227 and Np-237, as well as freshly separated standards. Please let us know if you are interested in any of these products and we can provide more information.

Within our range of stock solutions some of the products we provide are interference-free radionuclide solutions, covering measurement applications including naturally occurring radionuclides, decommissioning, environmental monitoring and nuclear forensics. These ultra-pure standardised solutions can be used for calibration of a mass spectrometer or alpha spectrometer for the radionuclide of interest prior to measuring unknown samples. They can also be used as tracers for radiochemical separation procedures. Our ultra-pure radionuclides can be found on the same list above.

Mixed Radionuclide solution

The NPL Mixed Radionuclide contains a set of radionuclides with fourteen gamma lines between 60 keV and 1836 keV. 

The relative activities of the radionuclides in the mixtures have been adjusted so that the relative intensities of the peaks in the gamma-spectrum are optimum at the reference date. If dilution is required, the NPL inactive carrier solution should be used, so that the radionuclides are not adsorbed on the walls of any vessels.   

The Mixed Radionuclide is available at three activity concentrations:    

NPL Product code R08-01: 500 g HDPE bottle, total activity 5 kBq 
NPL Product code R08-03: 10 g flame sealed glass ampoule, total activity 10 kBq  
NPL Product code R08-04: 10 g flame sealed glass ampoule, total activity 100 kBq 

The inactive carrier which should be used to dilute the Mixed Radionuclide solutions comes in just one size:

NPL Product code R08-Carrier: 500 g nominal

A limited quantity of the Mixed Radionuclide solution is prepared annually in the spring. Stocks will be allocated subject to receipt of purchase orders.  


Don’t see what you are looking for? Our diverse skill set enables us to provide bespoke solutions. Please contact us to discuss your requirements.

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