Quality Digest

Our company uses two types of calibrated metal rulers to measure parts, leadwires, etc. These rulers are used to make acceptance / rejection decisions on parts therefore, under ISO requirements they are on our calibration system.

PRECISION rulers - which are made of steel or glass with graduations that are permanently engraved, stamped, or molded.
NON-PRECISION rulers - which are made of aluminum, plastic, wood, etc. Graduations are applied by a non-permanent method such as silk screening, labels, etc.

The precision rulers are calibrated on a two year cycle because they do not wear out due to how they are made and marked.

The non-precision rulers are calibrated every year because they do wear out.

The question is in regards to the PRECISION RULERS. For the past ten years that we've been calibrating them, they have never been out of spec. and the markings have not worn out. Can these be excluded from the ISO calibration requirement due to the nature of how they are designed?