"Easy care", "non-iron", "wrinkle-free" — behind each of these claims there is usually one test: AATCC 124, Smoothness Appearance of Fabrics after Home Laundering, or its ISO counterpart, ISO 7768. The result is a grade from 1 to 5. It looks simple. It is also one of the easiest results to shift by half a grade without touching the fabric.
How the method works
Fabric specimens are laundered under defined home-laundering conditions — machine or hand washing, with a choice of cycles, temperatures and drying procedures — and then compared visually with a set of reference standards.
The references are three-dimensional plastic replicas, a set of six: SA-1, SA-2, SA-3, SA-3.5, SA-4 and SA-5. SA-5 is the smoothest; SA-1 the most wrinkled. Observers view each specimen between the most similar replicas under a standard overhead lighting arrangement in an otherwise darkened room, and select the replica it most closely matches.
Three trained observers rate each specimen independently, and the ratings are averaged. The 2009 edition used three 38 × 38 cm specimens per sample.
The method rates smoothness after laundering — the wrinkling that remains when a garment comes out of the wash and dryer. It is not the same as wrinkle recovery after creasing under load (AATCC 128 and ISO 9867), which answers a different question.
Trap 1: the viewing area
The grade depends on how the shadows of the wrinkles fall, so the lighting is specified, not left to the laboratory. The method uses a defined overhead fluorescent lamp arrangement above a grey viewing board, with all other lights off. AATCC also notes that light reflected from side walls near the board interferes with ratings, and recommends matte black side walls or blackout curtains. Observers stand at a fixed distance from the board.
Common deviations:
- Rating under the general room lighting, or with daylight from a window.
- A viewing board in front of a white or glossy wall.
- A colour assessment light cabinet used instead of the overhead arrangement. A cabinet is the right tool for colour work, but it is not the lighting geometry AATCC 124 specifies.
If your viewing area is not built to the method, your grades are not AATCC 124 grades, however carefully they are given.
Trap 2: one observer, or three who talk
The method's three observers are meant to be independent. In practice, one operator grades alone, or three people stand together and agree. Both reduce the method to one opinion.
Grade separately and record each observer's rating before discussing anything. Over time, track each observer's grades against the panel average: an observer who is consistently half a grade high is easy to spot, and easy to correct.
Trap 3: laundering creases counted as performance
Small specimens in a large washer and dryer can pick up sharp folds — washer and dryer creases — that a garment in normal use would not. The method treats these as artefacts, not fabric performance. It asks for folds to be removed by hand after washing, and for specimens creased after an intermediate drying cycle to be rewet and pressed before the next wash.
The same applies to drying. Overdrying makes lightweight specimens cling and stop tumbling, which creates exactly these creases. Take the load out when the dryer stops.
Trap 4: rating too early
Specimens are conditioned before rating. A specimen graded warm from the dryer, or still slightly damp from line drying, does not look the same as it will after conditioning. Rate conditioned specimens, at a consistent time after drying.
Trap 5: comparing results from different laundering conditions
AATCC itself notes that interlaboratory reproducibility depends on users agreeing the washing and drying conditions. The more severe Normal (Cotton Sturdy) cycle is generally considered the most appropriate for appearance retention; durable press cycles, with cool-down or cold rinses and reduced spin, are designed to minimise wrinkling. A "3.5 after Permanent Press" and a "3.5 after Normal" are not the same claim.
Machine parameters for AATCC home laundering now sit in AATCC LP1. Report the cycle, temperature, drying procedure and number of cycles alongside the grade.
Trap 6: prints
Prints and patterns can mask wrinkling. The method rates what the observer sees, pattern included, so a busy print can genuinely earn a better grade than the same base fabric in a plain shade. That is correct under the method — but it means a grade earned on a print should not be transferred to the plain colourways of the same quality.
Reporting checklist
- AATCC 124 (or ISO 7768) and edition.
- Washing cycle, temperature, drying procedure and number of cycles.
- Individual ratings of each observer, and the average.
- Viewing area built to the method's lighting arrangement?
- Any laundering creases removed, and how.
AATCC 124 shares its laundering with AATCC 135 and AATCC 179, so the same top-loading washer and tumble dryer serve all three. Our AATCC shrinkage washing machine, AATCC tumble dryer and wrinkle recovery tester are built in our own workshop in Istanbul.