This European Standard specifies methods for the chemical analysis of cement.
This standard describes the reference methods and, in certain cases, an alternative method which can be considered to be equivalent. It also describes methods which apply principally to cements, but which can also be applied to their constituent materials. They can also be applied to other materials, the standards for which call up these methods.
This major changes in this edition of the standard are:
a) BS EN 196-21 has been consolidated into BS EN 196-2
b) calibration against internationally accepted reference materials is permitted
c) the number of tests to be carried out, when the analysis is part of a series subject to statistical control, has been reduced to one
d) requirement for blank determinations has been included
e) limiting ranges have been set for masses, volumes and temperatures wherever these are significant
f) the required accuracy of the balance is consistent with that of equipment traditionally used
g) specification for a laboratory oven has been included
h) the calibration procedure for standard silica solution has been simplified
i) additional indicators have been included for the visual determination of EDTA titrations
j) an ignition temperature of (950 ± 25)°C has been set for the determination of loss on ignition and the ignition of barium sulfate and insoluble residues
k) determination of sulfate before and after ignition in the determination of loss on ignition becomes the reference method when correcting for sulfide
l) determination of silica by the double evaporation method becomes the reference method
m) in the determination of carbon dioxide by decomposition with sulfuric acid an additional, empty, gas washing bottle is included as a safety precaution against the reverse flow of sulfuric acid should pressure be lost
n) in the determination of alkali the influence of phosphoric acid on the potassium emission from the calibration solutions is suppressed by the addition of calcium to the calibration solutions.