Bis Standards For Vinyl Sulphone BIS has notified a new standard IS 18340:2023 for Vinyl Sulphone, a major intermediate for the manufacture of reactive dyes. This specification standardizes quality, purity, and safety of use for its use in the textile and the chemical industries. Position after Implementation of IS 18340:2023 Pre-verified Manufacturers of Vinyl Sulphone would require to get BIS certification before selling in Indian market. This certification goes beyond ensuring continued uniformity in product performance; it also communicates to end-users that the products meet strict national quality standards. Certified products will carry ISI Mark, which gives confidence to the customer on the quality of the product.