The program calculates the buckling capacity based on the Draft Amendments to BS 5950 "Structural Use of Steelwork in Building". Part 1:1990, Dated April 20^th 1998. In these proposed amendments, the calculation of an equivalent uniform moment factor, m_LT, has superseded the calculation of the slenderness factor n and the old equivalent uniform moment factor, m. The calculated value of m_LT is provided on all detail output.

The bending capacity of class 3 is considered to be the compression flange section modulus multiplied by the design yield strength.