Allowable bending stress for tension and compression for a structural member, as given in XVII-2214 of NF-3000 1974 is:

1. Along Major Axis:

2. For Compact Sections, tension and compression on extreme fibers of compact hot rolled or built-up members symmetrical about and loaded in the plane of their minor axes and meeting the requirements of Subsection NF shall result in a maximum bending stress:

   F_b = 0.66×F_y  

If meeting the requirements of this member of:

1. Width-thickness ratio of un-stiffened projecting elements of the compression flange shall not exceed 52.2/√F_y.

2. Width-thickness ratio of stiffened elements of the compression flange shall not exceed 190/√F_y.

3. The depth-thickness ratio of the web shall not exceed

   d/t = (412/√F_y)[1 - 2.33(F_a/F_y)]                  

   except that it need not be less than 257/√F_y.                                          

4. The laterally unsupported length of the compression flange of members other than box-shaped members shall not exceed the value of 76b_f/√F_y nor 20000/(d/A_f)F_y.

5. For noncompact and slender elements, clause XVII-2214.2 and XVII-2214.5 of NF-3000 1974 are followed respectively.

6. For box-type flexural members, maximum bending stress is:

   F_b = 0.60×F_y

7. Along Minor Axis:

   For doubly symmetrical members (I shaped) meeting the requirements of XVII-2214.1(a) and (b) of NF-3000 1974, maximum tensile and compressive bending stress shall not exceed:

   F_b = 0.75×F_y