Hi,
I don't really know about U.S navy protocol on this. I think Ray is on the right track though.
Most European navies did a routine called cleared for action, when going into battle.
This involved dropping/folding all stanchions and guard rails around heavy armament. Removing and stowing any light weight deck clutter, such as aircraft, shoring timbers, davit hung ships boats and other flamable or blast damageable items.
The thing to remember with heavy weapons is that when fired, the blast from the exhausting powder charges caused huge pressure waves ahead of the muzzles and a large vacuum effect behind them. Delicate structures and even deck planking or deck plates could get ripped up or buckled as a result.
If you wish to portray your wonderful model with the turrets in a firing postion, then it would make sense to have the main deck edge stanchions and rails folded flat as in the battle stations/cleared for action position.
regards
Ian