Table 19.
Expanded uncertainty (k = 2) in radiance temperature for a typical radiation thermometer. The uncertainty, in °C, is given for different radiance temperatures (also in °C)
| Source of Uncertainty | Type | Radiance temperature (°C) | ||||
|---|---|---|---|---|---|---|
| 800 | 1100 | 1500 | 1900 | 2300 | ||
| Calibration of the variable temperature blackbody relative to the 1990 NIST Radiance Temperature Scale | B | 0.2 | 0.3 | 0.4 | 0.6 | 0.8 |
| Mean effective wavelength measurement for the NIST PEP | B | 0.1 | 0.0 | 0.1 | 0.3 | 0.5 |
| Blackbody uniformity | B | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 |
| Test thermometer temperature determination | A | 0.6 | 0.6 | 0.6 | 0.6 | 0.6 |
| 1990 NIST Radiance Temperature Scale relative to thermodynamic temperature scale | B | 0.1 | 0.2 | 0.4 | 0.6 | 0.9 |
| Overall uncertainty of test radiometer calibration with respect to SI units | B | 0.7 | 0.8 | 0.9 | 1.1 | 1.5 |