A workshop coordinated by BIPM and held at NIST has given e-SI-Amp partners a chance to discuss how developments in small current measurement technology can be applied in the field of nuclear medicine.

The activity of samples of radioactive isotopes is a key tool in the development and application of certain cancer treatments. Activity is generally measured with ionisation chambers, secondary/transfer standards whose conversion efficiency is calibrated against primary standards. The electrical output of the chambers is a current, typically between 0.1 pA -1000 pA. Sufficiently stable and convenient electrical measurement instrumentation in this range is difficult to develop and operate. This is exactly the small current range and application that can be addressed by the technology in the e-SI-Amp project.

Representatives from NPL and PTB spoke on the subjects including:-

• The Ultrastable Low Current  Amplifier
• The limitations of capacitor ramp techniques for  traceable current measurements
• The stability of high value resistors in small current reference systems. 

For more information contact: stephen.giblin@npl.co.uk