This standard BS 6075-4:1981 Methods of sampling and test for sodium hydroxide for industrial use is classified in these ICS categories:
- 71.060.40 Bases
This International Standard specifies a reduced silico-molybdic complex photometric method for the determination of the silica content of sodium hydroxide for industrial use. The method is applicable to products having silica (SiO2) contents exceeding 10 mg/kg.
https://www.en-standard.eu/bs-6075-4-1981-methods-of-sampling-and-test-for-sodium-hydroxide-for-industrial-use-determination-of-silica-content/