This document specifies the reference method used for type testing and in cases of dispute, for the determination of the methylene blue value of the size 0/2 mm fraction in fine aggregates or all-in aggregates (MB). It also specifies the reference method for the determination of the methylene blue value of the size 0/0,125 mm fraction (MBF) in normative Annex A. Other methods can be used for other purposes, such as factory production control, provided that an appropriate working relationship with the suitable reference method has been established. Annex B specifies the preparation of 10 g/l methylene blue solution and Annex C specifies the procedure for the determination of the methylene blue value of kaolinite (MBk). Annexes B and C are normative. A conformity check, adding a single quantity of dye solution equivalent to a specified limiting value and which can be used as part of a production control process, is described in informative Annex D. An example of a test data sheet is given in informative Annex E. WARNING – The use of this part of EN 933 can involve hazardous materials, operations and equipment (such as dust, noise and heavy lifts). It does not purport to address all of the safety or environmental problems associated with its use. It is the responsibility of users of this document to take appropriate measures to ensure the safety and health of personnel and the environment prior to application of the standard, and fulfil statutory and regulatory requirements for this purpose.