BS 2690-104:1983

This standard BS 2690-104:1983 Methods of testing water used in industry is classified in these ICS categories:

• 13.060.25 Water for industrial use
• 13.060.50 Examination of water for chemical substances

The methods described are for the determination, in industrial waters, of reactive silica (spectrophotometry — reduced molybdosilicic acid), total silica (fusion and spectrophotometry) and suspended silica (filtration, fusion and spectrophotometry).

Section 104.1 Reactive silica: spectrophotometric method (reduced molybdosilicic acid)

Reactive silica by formation of molybdosilicic acid, reduction to molybdenum blue and spectrophotometric measurement. Applicable to up to 50 μg of SiO₂ in up to 100 ml. Total silica by prior fusion to reactive silica. Applicable to up to 50 μg of SiO₂ in up to 50 ml. Suspended silica by prior filtration and fusion. Applicable to up to 50 μg of SiO₂ in up to 1 L.