A: Machine Wash Cold or Warm. Do Not Bleach. Cool Tumble Dry or Hang. Remove Promptly. Use only Non-Ionic Detergents.
1. Detergents
Detergents contain enzymes, bleaches, surfactants, and builders.
The surfactants found in many detergents include anionic (negatively charged) alkalis that interact with water to remove oily dirt and stains.
However, these can strip ESD Garments of their positive ions leaving them predisposed to carrying negative charges. This is why it is recommended to not use detergents when washing ESD Garments.
However, if you feel you need to use detergents or fabric softeners, you should use liquid detergents that would be used on wool or silk since these do not contain alkalis. These are sometimes referred to as non-ionic detergents.
Non-Ionic detergents have a neutral pH (they are neither acidic nor alkaline) and produce electrically neutral particles when added to water.
2. Chlorine Bleach
Built in a grid pattern, the black carbon threading woven into ESD safe clothing shields nearby electronics from static on your clothes and skin underneath. This threading is what gives ESD safe clothes their conductivity and what makes your ESD garment “static shielding.”
Chlorine bleach attacks carbon bonds which in turn destroys this black carbon threading.
Non-chlorine bleaches are those used in “color-safe” commercial bleaches that are activated by contact with oxygen in the water. These are known as oxidizing bleaches: hydrogen peroxide, sodium percarbonate, and sodium perborate. While not as destructive to the carbon threading as chlorine bleach they are alkalines that can remove carbon with repeated use.
3. Drying
Carbon melts at 120 degrees Fahrenheit. This is why it is recommended to hang dry when possible. If not, tumble dry low in a dryer. If you are using an “industrial washing service” where the garments are run through heat tunnels the carbon in the garments may be altered after only one wash. You should periodically test the garment to make sure it is still working.
Conclusion
Whenever you clean an ESD smock in a washing machine, you are degrading the quality of it. Most ANSI / ESD S20.20 certified smocks can be washed only 90 – 100 times using non-ionic detergents before you need to buy a new one.
Further Reading
“The Chemistry of Stain Removal”, Compound Interest, Accessed 01/16/2018
“Understanding Detergent, Soap, Fabric Softer & Bleach”, The Laundress, Accessed 01/16/2018
