Erika SimmonsOctober 21, 2021 Press Release

When Do AATCC Scales REALLY Need to be Replaced?

The scales used by textile testing labs are carefully designed and checked for consistency, but they can change with time, exposure, and handling. There are some practical care and replacement guidelines for ensuring repeatable evaluations using AATCC scales.

Gray Scales

AATCC EP1 Gray Scale for Color Change and AATCC EP2, Gray Scale for Staining include an Appendix specifying the color difference for each chip pair and how to verify it.

Color difference for each pair of chips may be measured quarterly on a spectrophotometer with sphere geometry. Use a small area view (approximately 10-mm diameter) and specular component included. Be careful to position the scale so that only the desired chip is in the viewing area for each measurement. If ΔECIELAB is within the stated tolerance for all pairs, the gray scale is still suitable for use.

If you do not have access to a spectrophotometer or choose not to measure your scales every three months, replace each gray scale within one year of its initial use. For your convenience, there is a line on the scale to record the date of initial use. Of course, if there is visible damage to any of the chips or the mask, the scale should be replaced immediately.

Other recommendations for use and care are also listed on the scales and in the evaluation procedures.

  • Store scale in sleeve when not in use.
  • Do not place mask inside folded scale.
  • Inspect frequently for fingerprints and any other marks.
  • Replace annually or measure quarterly and replace as needed.

AATCC 9-Step Chromatic Transference Scale

Guidelines for the Chromatic Transference Scale are similar to those for the Gray Scales. AATCC EP8 states, “The cleanliness and physical condition of the Scale is extremely important in obtaining consistent results.”

  • Inspect frequently for fingerprints and any other marks.
  • Inspect for physical damage to the chips (e.g., chipped edges, loose or buckled chips).
  • Replace or measure at least annually on a spectrophotometer.


Spectrophotometer measurements can be particularly challenging on the chromatic scale because of the small chip size. The measurement area should not include any open area or adjacent chip. The viewing port diameter must be smaller than 10 mm.

Stain Release Scales

Stain scales for AATCC TM175, Stain Resistance: Pile Floor Coverings and AATCC TM130, Soil Release: Oily Stain Release Method should be replaced annually—more often if they are visibly soiled or damaged. To avoid premature color change, it is best to store both scales in a dark place between uses.

  • Inspect frequently for fingerprints and any other marks.
  • Store away from light.
  • Replace annually.

3D Appearance Replicas

The scales for appearance (wrinkle recovery, fabric smoothness, crease) evaluation are made up of three-dimension plastic replicas cast from fabric. While these are more durable than the printed scales, they still require careful handling and regular replacement.

  • Wipe with a damp cloth and allow to dry
  • Inspect frequently for marks, cracks, or other damage
  • Store replicas carefully in box slots.
  • Replace every three years.


Photographic Scales

Several AATCC test methods use photographic scales for evaluation. Some of these scales are mounted on rigid cards, while others are simply a sheet of paper.

  • Inspect frequently for marks, tears, scratches, or other damage
  • Replace every three years.




About AATCC: AATCC is the world’s leading not-for-profit association serving textile professionals since 1921. AATCC, headquartered in Research Triangle Park, NC, USA, provides test method development, quality control materials, and professional networking for members in about 50 countries throughout the world.


Media Contact: Erika Simmons, AATCC Technical Director; +1.919.549.3522;


BEST VIEWED IN CHROME AND FIREFOX BROWSERS. We use cookies to ensure that we give you the best experience on our website. By using our services, you agree to our use of cookies.