Thursday, October 8, 2009

Thekkady Boat Tragedy

Thekkady Boat Tragedy – Will we learn this time?

One more tragedy to this long list of mishaps that has been happening in Kerala waters - I am hoping that this is the tipping point for actions to prevent any future incidents to take place. These may include legislation to make stringent rules, execution to ensure that these rules are enforced, and a culture to follow the safety norms.

It would be unreasonable to pass any comments on how the tragedy occurred without going through the detailed investigation on the design, construction, testing, operation as well as the event itself. However, it would be appropriate to suggest a checklist for the investigating committee.

Let us go through the sequence of activities preceding the event on 30th September. The sequence would be something like this - boat design, construction, testing, and operation.

Starting with the boat design. Contrary to what some reporters on TV (with scant knowledge on what they are talking as well as a lack of desire to know them), fiberglass boats are not less safe just because they are light. A boat, irrespective of the material used (the strength rules are not standardized in case of wood), need to meet the requirements with respect to strength, stability, and performance. Just because the material (fiberglass) is light does not mean that the boat itself is less strong. Fiberglass as a material is stronger than steel for the same weight. Hence a same sized boat (same strength) would be lighter if made of fiberglass. With regards to stability, just because it is lighter it tends to have its center of gravity higher than steel boat, however, it still need to meet the requirements, compensating by a better hull shape or better distribution of weights.

Note that I stressed the material wood. There are no rules specifying the strength of such boats either in our Merchant Shipping Act (applicable for sea-going vessels) or in Inland Vessels Act (applicable for vessels plying in rivers, lakes, and other water bodies except sea). Let us forget these kinds of boats for the time being. That would be a digression from the topic in hand.

Coming back to fiberglass and steel boats, how many of us are aware that the Inland rules we follow in Kerala are the outdated Canal Act of Travancore Cochin States, which were more relevant in 1912 and not in this day. It even refers to Maharaja of Travancore and Cochin ! Our successive governments never bothered to have a proper Inland Water Rules applicable for vessels plying in Kerala waters. To the credit of the current government, and a possible outcome of the previous tragedy - Thattekad incident, there was an attempt to enact such a rule. There was a committee of experts and many organizations and experts contributed to prepare a draft rule that is now awaiting legislative approval. If that rules is enacted, and enforced, probably boats would be much more safer.

Talking further about the Canal rules, note that the rules specify only one relevant aspect to check ship's safety - freeboard. It does not have any means of checking the stability of a vessel. There are no test procedures for that. The stability test would include assessing the position of center of gravity of the vessel by means of an inclining experiment, further based on that result predict the static stability, dynamic stability (response to waves, wind and passenger heeling). Unfortunately the outdated Canal rules do not talk of any of these. So, when we say that, the boat has been tested as per the rules, then it is totally meaningless statement to assure us of its safety when the rules one speak of is the Canal rules of Kerala State .

Indian Register of Shipping (IRS), a third-party non-governmental organization that assesses and certifies the vessels strength and safety is another party in this whole chain. IRS has excellent rules for sea-going vessels and they have great experience in approving such designs as well as construction process. However, their Inland Vessel Rules are incomplete since it does not talk of vessel stability. That means IRS do not have clear criteria for inland vessels. So, again, when we say that a boat was built and certified as per IRS rules, then we can be assured of the vessels' strength, but we can never be sure of its stability. Only in scenario when the vessel is IRS built and registered with states that have their own reasonably adequate inland rules with respect to stability (like in case of Maharashtra) , we can be certain of stability aspect.

So, in short, when we assess the boat's design, we must check the following aspects. How was the vessels' stability assessed? In the design stage, we do a preliminary Stability assessment. In this, we estimate the center of gravity of the vessel, and check its static as well as dynamic stability for various cases. These cases ideally should reflect all possible scenarios that can happen to the vessel in operation. There was one gentleman (expert) who was quoted saying, "...since all passengers moved to one side because they saw something the boat toppled and capsized." I sincerely hope that he was misquoted. All passengers moving to one side is a very normal scenario in a passenger tourist boat (that is why they are going in the first place!). So, that means in our preliminary Stability assessment, this is a definite condition to check. If it is double decked (like in this case), surely, we can check what will happen if all passengers go up and move to
one side. That is why I mentioned- all possible scenarios should be evaluated.

Another important issue in the existing rules is the sub-division of vessel in to compartments. All of us are familiar with the scene in the Titanic movie when after the iceberg incident, the Ship's Naval Architect explains to Captain and Rose (Kate Winslet) how when water enters the compartments it gets filled and it overflows to the next until the whole vessel gets flooded. The lesson learnt in the incident was the importance of watertight bulkheads (it was 1912) and our rules still allows boats without sufficient watertight bulkheads (compartments) to ply. Most of the vessels plying in our backwaters are unsafe from this point of view and it is surprising despite knowing how fast a boat can sink if there is a damage in any one area!

Now coming to construction, there are various stages where compromises can be made in terms of the quality of materials used and method of construction. One way to ensure quality in these two is to have independent surveyors to do testing during construction as well as to assure of the material quality by testing. Our Canal rules nor the Irrigation department have means of ensuring that. So, a sub-standard vessel can easily pass through these processes and pass itself as a "safe vessel". IRS (or other Classification Societies), however, has a rigorous means to ensure quality of materials as well as process of construction. Hence if there is a certificate from IRS then we can be assured of the two areas.

Along with various other tests, one test that is most important one to assess the stability of the vessel is the inclining test. This is done after (most of) construction is complete and vessel is (nearly) ready. The previously calculated center of gravity is updated with this actual value from the test and the Final Stability analysis is done. Again in our Canal rule, there is no provision to perform this test and assess the stability. This test, though, is mandatory in case of vessel built under IRS. However, as explained above, the rules of IRS are inadequate to make the assessment for stability.

The next stage is the vessel during operation. Although in the design stage and construction stage (after testing) we can assure of the vessel strength and stability in a predicted scenario, it depends on the operators to follow the guidelines. Most of the operators do not understand the importance of capacity of a vessel - in case of cargo vessel it is the deadweight and in case of passenger vessel it is the passenger capacity. In either of the cases, when there is an overload, the vessel will immerse in water more than it is designed and two important effects can happen. One is with regards to strength. All the structure of the vessel is designed as per a draft (immersion level in water) called maximum draft. When the draft increases, the load on the vessel structure increases (as depth increases the pressure increases and therefore force acting on the vessel sides), and a scenario may happen that the structure may give way. In case of wooden boats, it
is usually the caulking between the planks that give way and water enters the compartment. The other aspect is with regards to stability. If a proper assessment was done in form of an authoritative Stability analysis, then when there is an overload, say 50% more, the whole scenario changes and the vessel may not be stable in a particular condition like all passengers moving to one side. That needs be ascertained. Other operational aspects include providing adequate number of life jackets and life buoys when would be inadequate when there is overloading.

The last important aspect is the safety culture. That is not a scope of this discussion, however, if people appreciate that, then surely many incident of overloading, under capacity of life saving equipments, etc. may not happen.

In this incident as well as other accidents, the common thread is the inadequacy of the rules. Our legislators must, instead of taking credit for rushing to the accident spot, pass the pending Inland Vessel Act, have a qualified Kerala Maritime Board, and save people from such unsafe vessels and avoidable accidents.

There are some of the aspects to be considered in this investigation and a detailed analysis would be taken up when sufficient data is available.

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