How It’s Tested: Episode 15 – Fabric Color Tests

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.

So far, our How It’s Tested series has covered everything from critical tests related to the protective qualities of arc-rated and flame resistant (AR / FR) garments, to why you should care about the tests your garments pass. Now, we’re diving into some topics that you might be less familiar with or not even considered; like color testing the fabrics used to make protective work wear. This post covers two tests that center around the color of your AR / FR garments when you receive them; crocking and color fastness.

Watch as VP of Technical, Scott Margolin, explains these two tests in detail: 

What is the Crocking Test?

Crocking of either wet or dry fabrics, refers to the rubbing off of color from a fabric when subjected to abrasion. The point of the crocking test is to see how much color is transferred from a new color-dyed fabric, either wet or dry, on to another fabric.

You may have experienced this with heavily dyed indigo denim – it wears off on our hands while wearing the denim or other fabrics when being washed. We use the crocking test to evaluate the level of dye a fabric transfers. The test is performed by rubbing a white test square against the wet or dry dyed fabric. The amount of color transferred to the white test square is then graded on a scale from 1 to 5, with 1 being the highest degree of color transfer and 5 being no color transfer.

Crocking Test Grading

In all cases of crock testing fabrics, the higher the grade the better. This is to avoid the dye transferring to your hands, other clothes, or anything else in your washing machine.

But what about just normal launderings? You may wonder, will my clothing fade just from washing it? This is where the color fastness test comes into play.

What is Color Fastness to Laundering?

AATCC 61 Method 2A looks at whether the fabric color your garment is when you bought it is maintained throughout multiple launderings. This method enables us to test for color loss and surface change by using a detergent solution and abrasive action to evaluate color fastness in an accelerated manner. This test is designed to replicate 5 home laundering procedures at a medium or warm setting (100F° +/- 5°F).

How is color fastness measured?

After laundering, the fabric is dried, conditioned, and evaluated with both the Gray Scale for Color Change and the Gray Scale for Staining.

While the color of your AR / FR garments doesn’t change the clothing’s protective features, it does contribute to our overall satisfaction. Maintaining the color of a garment is important for getting the most out of your AR / FR clothing.


Series: How It's Tested - All Things Testing

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