The raw material used for production of IAEA-479 was high quality milk powder (26% fat content) without detectable radio-caesium and radio-strontium isotopes. The raw material was spiked with radionuclides, using dilutions of high precision radioactive certified reference solutions from metrological institutes. After spiking, it was homogenised and tested for heterogeneity. The particle size distribution of the material is between 50 and 280 µm (at 10 % and 90 % cumulative percentage, respectively).
Reference date for all specified radionuclide decay corrections: 01 January 2020
Certified values for activity concentration
(based on dry mass)
| Radionuclide | Certified value⁽ᵃ⁾ [Bq Kg⁻¹] | Uncertainty⁽ᵇ⁾ [Bq Kg⁻¹] | Half-life | Remark⁽ᶜ⁾ |
| ⁹⁰Sr | 41.2 | 1.0 | 28.80 (7) y | (N) |
| ¹³³Ba | 30.3 | 0.7 | 10.539 (6) y | |
| ¹³⁴Cs | 213.0 | 4.7 | 2.0644 (14) y | |
| ¹³⁷Cs | 228.6 | 5.0 | 30.05 (8) y | |
(a) Certified values are calculated based on material balance following ISO Guide 35.
(b) The uncertainty is expressed as a combined standard uncertainty (coverage factor k = 1).
(c) The property values annoted (N) are not within the scope of accreditation.
Information values for activity concentration
(based on dry mass)
| Radionuclide | Information value⁽ᵃ⁾ [Bq Kg⁻¹] | Uncertainty⁽ᵇ⁾ [Bq kg⁻¹] | Half-life | Remark⁽ᶜ⁾ |
| ⁴⁰K | 378 | 15 | 1.2504 (30) x 109 y | (N) |
(a) Information values are calculated from the accepted data sets, being obtained by one laboratory following ISO Guide 35.
(b) The uncertainty is expressed as a combined standard uncertainty (coverage factor k = 1 ).
(c) The property values annoted (N) are not within the scope of accreditation.
