This International Standard specifies a method of test for determining the resistance of flat surfaces of vitreous and porcelain enamels to pure boiling citric acid.

It is especially intended for the testing of enamels for articles which are used with boiling, slightly dissociated acids, for example cooking utensils.

This method of test is not suitable for enamels used in the chemical industry or those exposed to heavy attack by inorganic acids for a long period.

For testing enamels at room temperature, see ISO 2722.

For testing acid resistance of enamels for containers and apparatus for the chemical industry, see ISO 2743.