scope:

Specifies methods for the measurement of the hydroxyl number of polyols used as polyurethane raw materials. Part A is primarily applicable to readily esterified polyether polyols. It is also recommended for polyols which have significant steric hindrance, such as those based on sugars. Part B is recommended for polyether polyols, polymer polyols, and amine-iniated polyols, but maygive low results for sterically hindered polyols. Other polyols may be analyzed by these methods if precautions are taken to verify applicability.