The outer door has a sign saying the door shouldn't be opened except when the ship is in port. The door is opened by rotating the large round handle in the middle (and then rotating the other direction to close the door).
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/98147195@N00">mark6mauno</a>
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/mark6mauno/4204135352/">Outer door to Forward Balcony</a>