Urea for industrial use — Measurement of the variation of pH in the presence of formaldehyde — Potentiometric method

Specifies the principle of measurement, at (20 0.5) 0C, of the quantity of 0.01 N sodium hydroxide standard volumetric solution required to take the pH of a solution containing 50 g of sample in 100 ml of water to a pH of 8.3 after addition of formaldehyde. Has also been approved by the IUPAC.