Why the final rinse needs an acid sour
The text in the pictures is in Thai, as originally posted.
🧪 "A clean-water rinse is enough, nothing needs adding to the final rinse." Is that true?
Should a mild acid neutralizer (sour) be added to the final rinse in laundry work?
This is just a common belief. According to the US CDC guidelines for environmental infection control, the mild acid in the final rinse neutralizes alkali left in the fabric, which helps reduce skin irritation from alkaline residue. The CDC explains in general terms that the pH shifts from around 12 to around 5, but this is an illustration, not a target value for any particular product. What owners should do is ask their chemical supplier about the type and amount that suits their wash formulas. Always follow the machine manual.
Questions about chemical settings on your washers? The KHT team is happy to advise.