Specifies requirements for design and construction of pressure vessels in which material design strengths higher than those specified in AS 1210 are permitted. It applies only to static vessels, and specifies only those requirements which differ from or are additional to the requirements for Class 1 vessels in AS 1210. Two new classes (2HA and 2HB) of vessels are introduced.With the changes introduced by Amendment No. 2, this 1990 edition of AS 1210 Supplement 1 is suitable for use with the 1997 edition of AS 1210, Pressure vessels.