Passenger of size

[dramajoy]

Just wondering what the guidelines are for a fellow passenger of size who encroaches on another passengers seat while lifting the arm rest.  The passenger "asked" to remove armrest, however it was more of a rhetorical question as she did not wait for an answer and lifted it anyway. 

[franktravel]

The armrest is the definitive gauge for a Customer of size. It serves as the boundary between seats; the width between armrests measures 17 inches. Customers who are unable to lower both armrests and/or who encroach upon any portion of the adjacent seat may proactively book the number of seats needed prior to travel or receive a complimentary additional seat.