This specification provides standard dimensional requirements for flat-bottom and round-bottom glass boiling flasks. Boiling flasks shall be in the following types: type I – flat bottomed: class 1 - tooled top, long neck; class 2 - ring neck, long neck; class 3 - ring neck, long neck, wicker protector; class 4 - standard taper neck, short neck; class 5 - standard taper neck, long neck. Type II – round bottomed: class 1—tooled top, long neck; class 2—ring neck, short neck; class 3—standard taper neck, short neck; class 4—standard taper neck, long neck; class 5—standard taper neck, short neck with side arm; class 6—standard taper neck, short neck with thermometer well; and class 7—ball and socket neck, short neck. Type III – heart-shape bottomed: class 1—standard taper neck, short neck. Necks on all single-neck flasks shall be circular in cross section and perpendicular to the center of the flask body. The top shall be strengthened and finished. Flat bottoms shall be in a plane perpendicular to the vertical axis through the neck of the flask. Round-bottomed flasks shall be spherical in shape to the point of juncture with the flask neck. The nominal capacity of a flask shall not exceed the actual capacity to the base of the neck.

1.1 This specification provides standard dimensional requirements for flat-bottom and round-bottom glass boiling flasks.

Note 1: For packaging standards, choose among the following standards, E920, E921, E1133, and E1157.

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.