You can certainly use the B&L for calibrating work, but we cannot guarantee its accuracy for certification work. Keep in mind that Bausch & Lomb Lenscope Magnifier has a small lens of 15.8mm and the Bausch & Lomb Measuring Scales are not designed to be used without the magnifier and also, that the scales are sold separately. They are not included with the magnifier. _________________ Thanks for posting with us
Joanie K - Your personal optics expert