I believe everyone has at some point travelled with a ferry, a yacht or a cruise ship and there was a moment that had to walk on the promenade, enjoy the sunshine, the scenery or simply get some fresh air. Open deck is an essential part of ships, which necessitates protection from falling over, therefore some sort of railing is available on all open decks. This railing is simultaneously supporting our passage during an unfavourable weather and aids people with walking challenges. For cruise ships and yachts it serves an additional aesthetic aspect, characteristic trivial for authorities but important for guests. When looking at a mega yacht it is proportionally small to notice from far, but for the passenger on board it is front view. On the other hand for a small cruiser, the height makes it quite prominent and it is interesting to see that it is missing from the presentation of most initial concepts.
There are three main types of structural members composing the deck boundaries, i.e. bulwark, railing and balustrades, along with any combination of the aforementioned. Focusing on the bulwark is a continuation of the hull structure in the same material and stiffening concept. On small ferries traveling around the greek islands, the stiffeners can been seen from inside, but on a luxury yacht they are covered with internal panels for a more beautiful end result. Still there are the necessary openings, like freeing ports and fairleads, made of polished stainless steel adding a beautiful feature in the area. As per guidelines, these structures have a height of 1m (or exceptionally 915mm) measured from the deck to the top of the grab rail, which is sufficient to cover an adult or teenager, but it is spoiling the fun of many younger children that peep through the fairleads or try to climb it.
As mentioned before, another form of protection is the railing, an assembly of stanchions fitted at right intervals, supporting the grab rail on top and having horizontal intercostals to prevent a person from falling over through the deck and grab rail. For yachts they are made of stainless steel and have different shapes to intrigue our eyes, though not so versatile as the respective ones for houses’ balconies. It is very interesting to mention that steel wire ropes are permitted in lieu of the grab rail or horizontal divisions, but must be taut with turnbuckles.
Mentioned last but for many the preferred option, are the balustrades, transparent glass railing that gives the required protection without obstructing the view. Picture yourself lying on the sundeck, sunbathing, and being able to watch your friends playing their water sports or simply enjoying the nearby beach. As in the case of the railing, they need to be supported by stanchions and only laminated toughened glass is permitted, reviewed as a window under weather and personnel loads. The type of glass and manufacturing method is subject to approval, yet batch testing for standard glass types is also acceptable.
Having established the fundamentals of the railing onboard, there are some interesting facts that have captured my attention.
- Bulwarks’ structure is reviewed as part for the hull structure, the area of the freeing ports is examined to ensure water is not trapped on deck, while the height and extent is also taken into consideration;
- Balustrades have to follow strict review for strength and manufacturing process, matching the windows’ process. Especially chemically toughened glass goes under the magnified glass, as its additional strength is gathered at the external layers and a scratch is believed to diminish its advantages. It is important to note that this scratch might not be visible to the naked eye. Needless to say that the distance between the stanchions, their height and extent are also noted;
- Similarly to the aforementioned types, the railing assembly is examined in respect of the stanchions’ distance, the gap between grab rails and intercostals, overall height and coverage of the open deck. Dissimilarly to the previous two means of protection it is not reviewed for strength, i.e. establish the yield strength of the stanchions, although there is a minimum dimension for a pipe given for the grab rail;
- Moreover steel wire ropes are acceptable in lieu of fixed grab rails and better received from authorities that glass panels. Indeed steel wires are type approved and their strength is defined but the feeling they give is definitely not equivalent to a solid option like railings or balustrades. For a child, glass can be a real barrier, he/ she can’t climb on it nor can try to go through in-between. I respect that it is more likely to lean on a glass panel than a wire, but could it be that we are more accustomed to wires than glass?
- It is generally acceptable that for yachting railing or balustrades are an aesthetic feature, but when looking at railing for balconies, it seems that creativity has gone a lot further. How come?