Each meter is equipped with two test standards with light transmittance values printed on their labels, These values are accurate to within plus or minus one percentage point of a N.I.S.T. calibrated spectrophotometer.
To verify The Tint Meter is working properly and within specifications, take a reading of the reference samples before you begin to use the Tint Meter. The meter should display a reading of not more than plus or minus 3% points of the value printed on the label.