Fitting of seats

(1) No part of the back of any seat placed lengthwise shall be less than 54" from the corresponding part of the seat facing it. (2) Traverse seats shall be so fitted that– (i) when facing in the same direction, there is a clear space of at least 24" in front of every part of the top of the seat back, any handles or grips which do not project more than 4'' from the back of a seat being disregarded when measuring the clear spaces herein referred to; (ii) when facing each other, there is a clear space of at least 19'' between any part of the front of a seat and any part of any other seat which faces it.