Our How it's Tested series explores safety standards and test methods for AR / FR garments and PPE. With Scott Margolin, Vice President of Technical as our guide, we examine many of the major tests to understand what they measure, how they measure it, and what that means to someone like you who is specifying or wearing the garment. Whether you are a seasoned professional or just starting out, explore all episodes in this series to make sure you are up to date on the latest information.
If you’ve been following our How it’s Tested series, you’re aware of the four (4) main NFPA 2112 tests. But, did you know there are a dozen other tests that help determine garment performance? Today we’re diving into some of these other tests, and explaining why they are so important.
Let’s join Scott Margolin, Tyndale’s Vice President of Technical, as he helps us understand the importance of these other tests.
Let’s get started with Thread Melting
Thread melting is an important test for arc rated and flame resistant (AR / FR) clothing. This is a pass/fail test, where the FR thread used to make AR / FR garments must not melt below 500°F. This test is performed by putting a small sample of FR thread into a testing apparatus and exposing it to a temperature of 500°F. If the thread melts before reaching 500°, the thread fails and cannot be used for AR / FR garments.
Next up: Measuring Fabric Weight
Although this is not a “test” of NFPA 2112, we are required to measure the fabric weight. These measurements are reported in ounces per square yard and are extremely relevant when conducting other NFPA 2112 tests to ensure accurate results.
The Four Mechanical Strength Tests
The mechanical strength tests measure durability of fabric. We’ve outlined the four tests here with helpful links for more information
- ASTM D5034 – Standard Test Method for Breaking Strength and Elongation of Textile Fabrics.
- Also known as “the break test,” this test is used to determine the force needed to break a fabric that is being held at the top and bottom.
- ASTM D1424 – Standard Test Method for Tearing Strength of Fabrics by Falling-Pendulum (Elmendorf-Type) Apparatus. This test, known as the “Elmendorf tear,” tests the strength needed to propagate an existing tear.
- ASTM D3787 – Standard Test Method for Bursting Strength of Textiles – Constant-Rate-of-Traverse (CRT) Ball Burst Test. Known as “the burst test,” the point of this test is to mimic a knee or elbow coming through the fabric.
- ASTM D1683 – Standard Test Method for Failure in Sewn Seams of Woven Fabrics. Very similar to ASTM D5034 (“the break test”), this test is performed on a seam to determine the force required to beak either the seam or the fabric.
Laundering and Color Fastness
The last of the remaining tests we’ll discuss focus on laundering and colorfastness. The American Association of Textile Chemists and Colorists (AATCC) has created these tests to ensure garments retain their correct size and color properties when laundered.
Scott Margolin has outlined these AATCC tests in video form. Let’s watch him break down laundering and colorfastness testing concerning NFPA 2112.
- AATCC TM135 – Dimensional Changes of Fabrics after Home Laundering. This test measures the shrinkage due to laundering after several wash cycles.
- AATCC TM61 – Colorfastness to Laundering. This test measures the degree of color change due to laundering, by grading color loss, with five (5) being the least color change, and one (1) being a significant color change. The same test is run against dry cleaning.
- AATCC TM8 – Colorfastness to Crocking: Crockmeter Method. ATTCC TM8 measures the amount of color that is transferred from a material to a white surface due to rubbing or abrasion.
- AATCC TM16.3 – Test Method for Colorfastness to Light: Xenon-Arc. This test measures color loss in a piece of fabric due to exposure to sunlight. In this test, a xenon arc lamp is used to simulate years of sunlight in only two weeks.
Last but not least, let’s discuss labeling and label readability. After a garment passes all the various 2112 tests, it is subjected to a label legibility test. To accomplish this, the label is subjected to 100 launderings. After 100 launderings have been performed, the label must remain legible from one (1) foot away.
We realize there is a lot to take in here. But by understanding what these tests are and why they are important, you gain peace of mind that all this testing is required to keep you safe and certain that your garment will perform as expected.