Section 17(4) in The Railways (Opening for Public Carriage of Passengers) Rules, 2000
(4)(a)When making Card Deflection Test, the test cards are to be placed at right angles to the centre line of the track, in order to record oscillation and the recording pencil point should be as fine as possible.(b)When central deflection is measured, allowance shall be made for the deflection, if any, of the abutments.
