NATA class of test 1.64.02
Illuminance meters can be calibrated for
Responsivity CIE Sources A and C
The results are normally given in the form of a correction factor rather than adjusting the readout.
Up to 10 000 lux with a least uncertainty of 1.2%
>10 000 to 50 000 (not part of a NATA endorsed report) with a least uncertainty of ?%
Spectral responsivity (broadband method)
Based on sources calibrated by the National Measurement Institute, Australia.