Measurement
Quantity/Unit | Range | Best measurement capability (k=2) | Used at calibration of e.g. |
| Spectral reflectance in different geometrics *) | 0.5-100% | 2.0% | Calibration standards for spectral measurement instruments |
| The coefficient of specific retroreflection R' | 3-106 cd/(lx x m2) | 3.2% | Retroreflecting materials |
Retroreflection
coefficient RL | 130-180 mcd/
(m2 x lx) | +/- 5 mcd/(m2 x lx) | Road measurement instruments (LTL800, LTL 2000, LPL 2000SQ, LTLX) |
| Mean luminance coefficient QD | 50-200 mcd/
(m2 x lx) | +/- 4 mcd/(m2 x lx) | Road measurement instruments
(QD30) |
| Luminuous flux | 5-20.000 lm
50-50.000 lm
250-6.000 lm | 1.1%
1.5%
1.2% | Incandescent lamps
Discharge lamps
Fluorescent tubes/lamps |
| Luminous intensity | 1-106 cd | 1.6% | Luminous intensity standards |
| Illuminance | 1-700 lx | 2.3% | Illuminance standards |
| Luminance | 0.15-1.500 cd/m2 | 2.8% | Luminance standards |
| Illuminance | 1-2500 lx | 2.2% | Illuminance meters |
| Luminance | 3-750 cd/m2 | 1.8% | Luminance meters |
| *) | The results are stated for 10o
respectively 2o standard observers
according to the following colorimetric systems:
CIE 1931-x,y and Y
CIE 1976 UCS -u' and v'
CIELAB - L*, a*' and b*
at the standard light types A,C and D65 |  | | |
Testing
Aircraft and airport noise
