2018JIS K 1603-2 AMD 1:2018 Plastics -- Aromatic isocyanates for use in the production of polyurethanes -- Part 2: Determination of acidity (Amendment 1)
2007JIS K 1603-1:2007 Plastics -- Aromatic isocyanates for use in the production of polyurethanes -- Part 1: Determination of isocyanate content
1985JIS K 1603:1985 Testing methods for polymethylene polyphenyl polyisocyanate (testing methods for polymeric MDI)