Section 172(e) in The Delhi Building And Other Construction Workers (Regulation Of Employment And Conditions Of Service) Rules, 2002
(e)every ladder is -(i)secured so as to prevent undue swaying;(ii)equally and properly supported on each of its upright;(iii)so used as not to cause undue sagging; and(iv)placed as nearly as possible at an inclination of four in one;
