NATA class of test 1.65.08
ORLAB is NATA accredited for calibration of transmittance densitometers including vertical light path photometers
Least uncertainty of measurement vary depending on wavelength band, method used and value of transmittance
These measurements are used to characterise filters for calibrating spectrophotometers, transmittance densitometers etc and also for measuring products such as protective filers and window glass
Based on filters calibrated by the National Research Council of Canada.