Methodology for preparing a reference sample in the air filter matrix

Abstract

The proficiency tests are widely used to evaluate the analytical capacity of laboratories and also as part of the accreditation processes. The National Intercomparison Program is a Proficiency Test that uses radioactive    reference materials in soil, vegetation, water and air filters. This work is a study of the choice of composition of radionuclides ideal to be used in the air filters to be produced by LNMRI as reference material for PNI. Five cocktails composed of different radionuclides chosen for their energies in the range of 30 to 2000 keV were prepared, each cocktail was distributed in three glass fiber air filters using a pantograph using the pycnometer technique, contaminating each filter with 19 (nineteen) drops, totaling fifteen (15) air filter samples, with the objective of homogeneous distribution of the droplets at the sites determined by the geometry chosen without the need for marking in the filters, in order to choose the best composition to be used in the preparation of reference material.