The issue with safe standing is the potential obstruction of sight lines of the pitch which is why the two existing quadrants would work. However they may not be the most favoured location. If you were to do it in the Devonport for example you would have to extend it around the adjoining quadrant for the same number of rows to maintain sight lines..
Safe standing solutions are evolving. They do not give additional capacity as the same width seat has to remain an option. At Chelsea the standing rails were retrofitted and worked because the rake of the seating tier, particularly in the upper tier, allowed good visibility even if you were sat down. The 'horseshoe' does not have the same steep rake so a bespoke solution is probably required (See below). That is why the Club have not yet replaced the seating at the Devonport and Barn Park ends as the safe standing seating is a new and more expensive solution for no financial gain in ticket pricing.
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