These flasks are designed for the determination of phenols in essential oils, light oils, middle oils and creosote oils and for the determination of aldehydes and ketones. They are also used for other applications where a lighter fraction separates out of a solution and requires a volume measurement in situ.
For basic measurement of liquids in qualitative work a Class B flask is sufficient. For more accurate measurement of liquid a Class A flask is appropriate. Class A cylinders are calibrated to half the tolerance of Class B cylinders and each has a unique serial number for traceability. A certificate of accuracy traceable to national standards can be provided if required. Class A cylinders are used in analytical labs, quantative labs, and other controlled environments.