Apparel testing is essential before shipment to foreign countries like the US and EU. Selection of a suitable testing lab is required to get the right result. In order to achieve this, the lab has to equip themselves with equipment, calibration, proficiency testing, training etc. Such aspects have been critically reviewed in this paper.
Merriam-Webster defines “proficient” as “good at doing something” or “well advanced in an art, occupation, or branch of knowledge”. These all sound like good attributes to look for when selecting a lab to do textile testing. But how does one know if a lab is good at doing something—specifically the tests one wants to be performed? How can one tells if technicians have advanced knowledge of the tests?
One way labs can measure their performance is by participating in proficiency programs. Proficiency programs allow labs to anonymously compare their results to those of tens, or even hundreds, of other labs.
Each participant performs the same test on specimens of the same fabrics. Results are compiled and reported back to the participants.
For instance, in the case of AATCC Proficiency Testing Programs, each participant is assigned a number, known only to themselves. Tables and graphs are distributed so each lab can see how its results compare to those of others and determine whether additional training is needed on particular test methods.
Example of test method results graph given in Figure 1:
Participants in AATCC Proficiency Testing Programs receive a certificate each year. The certificate doesn’t guarantee that the lab did the tests correctly, but it does show an effort to monitor and improve performance.
Certificates from these and other proficiency programs may be on display in the lab. If not, one can ask if the lab participates in such programs, how frequently, how recently, and for which test methods.
Examples AATCC Proficiency Testing Programs are given below
|Antibacterial||TM100, Antibacterial Finishes on Textile Materials: Assessment of
TM147, Antibacterial Activity Assessment of Textile Materials: Parallel Streak Method
|Appearance & Physical Properties||TM88B, Smoothness of Seams in Fabrics after Repeated Home Laundering
TM88C, Retention of Creases in Fabrics after Repeated Home Laundering
TM124, Smoothness Appearance of Fabrics after Repeated Home Laundering
TM135, Dimensional Changes of Fabrics after Home Laundering
|Colourfastness||TM8, Colorfastness to Crocking: Crockmeter Method
TM15, Colorfastness to Perspiration
TM16.3 Option 3, colorfastness to Light: Xenon-Arc
TM61, Colorfastness to Laundering: Accelerated
TM107, Colorfastness to Water
|Fibre Identification & Analysis||TM20A, Fiber Analysis: Quantitative
Visual Gray Scale for Color Change Evaluation
Evaluation Procedure 1, Gray Scale for Color Change
|Water Resistance/Repellency||TM22, Water Repellency: Spray Test
TM35, Water Resistance: Rain Test
TM42, Water Resistance: Impact Penetration Test
TM127, Water Resistance: Hydrostatic Pressure Test
Verification of Fabrics
Formal proficiency programs aren’t the only way for a lab to stay on track. Purchased or in-house verification, or control, fabrics also help “verify” proper testing. These fabrics have a known value for a specific test. If the operator gets that value, he or she has probably performed the test correctly and can proceed with the evaluation of test specimens.
Examples of verification fabrics include AATCC Blue Wool Lightfastness Standards for Test Methods 16.1, 16.2, and 16.3, Colorfastness to Light;
One “right” answer doesn’t necessarily make a lab, or even that technician, proficient. And one “wrong” answer doesn’t mean one shouldn’t use the lab. With regular use of proficiency programs and verification fabrics, a lab is alert to potential problems before they affect customers’ results. Proficiency programs and verification fabrics are not used in isolation.
Calibration of the apparatus and training of staff are also part of the equation.