Aqueous Urea Solutions

Calibration and Services

Refractometer Calibration

“RI Equivalent” Aqueous Urea Solutions 

ILAC - MRAUsers of refractometers for the testing of Diesel Exhaust Fluids require some specific calibration materials. Manufacturers need an extremely high accuracy CRM to comply with ISO 22241-2, whilst users in the field need longevity of product.

Bellingham + Stanley offers an existing fluid that has an equivalent refractive index to 32.5% Urea.

Manufactured in accordance EN ISO/IEC 17025:2005, this CRM is supplied with a UKAS Certificate showing traceability to NIST and ICUMSA at 20°C and 589nm.

Order Code Type Value (RI) Vessel Volume Uncertainty
(RI: k=2)
Shelf Life
90-421 BS-AUS 1.38290 Glass 1 x 5ml ±0.000034 12-months
90-521 BS-AUS 1.38290 Glass 5 x 5ml ±0.000034 12-months

The reported expanded uncertainty of measurement is stated as the standard uncertainty of measurement in units of °Brix (equivalent to weight % sucrose in water) multiplied by the coverage factor k=2, which for a normal distribution corresponds to a coverage probability of approximately 95%. The standard uncertainty of measurement has been determined in accordance with publication EA-4/02.