2006 New York Code - Thin Concrete Shells.

 
    § 27-634 Thin concrete shells. The provisions of sections 403, 404 and
  405  of  reference  standard  RS  10-45  shall  apply with the following
  modifications. The remaining sections of  reference  standard  RS  10-45
  shall not apply.
    (1)  The  advisory  provisions of this standard shall be considered as
  mandatory.
    (2) The minimum ultimate strength of concrete for thin shells shall be
  three thousand psi.
    (3) Change all references to  "the  building  code  (ACI  318-63)"  to
  "reference standard RS 10-4".