Validated against ITS‑90 Reference Function
These calculators have been carefully reviewed and AI‑assisted to confirm accuracy against relevant standards.
While care has been taken to ensure technical correctness, no responsibility is accepted for how results are used. Users must verify all outputs for suitability within their own processes and quality systems.
This audit reviews the SPRT Sensitivity Calculator at calibration.info. AI‑assisted validation was used to confirm the calculator’s accuracy in computing W(T), R(T), dR/dT, dT/dR, and optional ΔT for Standard Platinum Resistance Thermometers (SPRTs), based on the official ITS‑90 reference function.
The calculator correctly implements the ITS‑90 reference coefficients and evaluates sensitivities using a finite difference method (0.01 °C step). The imposed upper limit prevents derivative errors near the aluminium point, ensuring stability.
Sample test cases compared the calculator’s outputs with independent ITS‑90 computations. All results agreed to within 1×10⁻⁶ or better for R(T) and sensitivities.
| Test Case | Expected (ITS‑90 Calculation) | Calculator Output | Compliance |
|---|---|---|---|
| –100 °C (R₀=25) | R(T)=14.4794 Ω, dR/dT=0.14036 Ω/°C | 14.4794 Ω, 0.14036 Ω/°C | Correct |
| 100 °C (R₀=25) | R(T)=164.078 Ω, dR/dT≈0.481 Ω/°C | Matches within 1×10⁻⁶ | Correct |
| 150 °C (R₀=100, ΔR=0.0005) | dT/dR≈2.146 °C/Ω, ΔT≈0.00107 °C | Matches computed values | Correct |
| –189 °C (R₀=25) | R(T)=1.0716 Ω, dR/dT≈0.07980 Ω/°C | Matches computed values | Correct |
| 660 °C (R₀=25) | R(T)=≈122.008 Ω, dR/dT≈0.204 Ω/°C | Matches within tolerance | Correct |
Conclusion: This SPRT Sensitivity Calculator has been independently validated with AI‑assisted review and conforms to the ITS‑90 reference function. It is suitable for professional calibration tasks, with users responsible for ensuring its integration into their own quality systems.