Bis Certification For H acid IS 8637 H acid, also known as 1-amino-8-naphthol-3, 6-disulfonic acid, will soon require BIS certification for both local and foreign manufacturers as per the BIS quality control order. H Acid is a key intermediate chemical used mainly in the production of azo dyes, which are widely used in textiles, leather, paper and various other industries. IS 8637:2020 outlines the quality, safety and compliance of H Acid to industry standards. Manufacturers must obtain a license from the Bureau of Indian Standards (BIS) and display the standard mark (ISI Mark) on their H Acid products.