Important as lifeboats and liferafts are, most crew and passengers on ships would rather they remained unused. However, they are a necessary last resort for those on board and over the years many have been grateful that they were provided.
The launching arrangements for survival craft are contained in SOLAS Chapter III Regulation 16 and the carriage requirements for passenger ships and cargo ships in Regulations 21 and 31 respectively. SOLAS requires that there be sufficient lifeboats on board passenger ships to accommodate all persons on board; half being placed on each side of the vessel. At the discretion of the flag state, the lifeboat capacity on each side can be reduced to 37.5% of the total number on board with the shortfall being made up with liferafts. For passenger vessels on short international voyages, it is permissible for the lifeboat capacity to be reduced and the deficiency replaced with liferafts. In all cases there must also be additional liferaft capacity to cover 25% of the total on board.
For cargo vessels, the requirement is for a lifeboat on each side capable of carrying all persons on board and liferafts for the same number. If the liferafts can be transferred from side to side the requirement can be met with one set of liferafts. In case a stern free-fall lifeboat is fitted, the requirement for capacity for all on board on each side is removed but the requirement for liferafts remains unchanged. The liferaft or liferafts must be equipped with a lashing or an equivalent means of securing it that will automatically release the liferaft from a sinking ship.
There are special requirements in SOLAS for certain vessel types when the normally-required enclosed lifeboat is replaced by a more specialised alternative. Chemical tankers and gas carriers carrying cargoes emitting toxic vapours or gases require lifeboats with a self-contained air support system complying with the requirements of section 4.8 of the LSA Code. For oil tankers, chemical tankers and gas carriers carrying cargoes having a flashpoint not exceeding 60ºC (closed-cup test) the rule is for fire-protected lifeboats complying with the requirements of section 4.9 of the LSA Code.
The issue of ensuring a safe atmosphere inside an enclosed lifeboat is not necessarily confined to vapours from cargoes. The oxygen inside a totally enclosed lifeboat occupied by a full complement of crew and/or passengers could soon become depleted without adequate ventilation. At the SSE 5 meeting in March 2018, it was agreed that a requirement for a ventilation rate of at least 5m3/h per person to comply with the expected performance should be set. In this regard, a new paragraph under 4.6.6 of the LSA Code was drafted and adopted at MSC 100 in December 2018.
Supplied for survival
Lifeboats are considered essential items of ships’ equipment and although there has been an extended period with few, if any, instances of crew having to survive for a long time in lifeboats, there is no guarantee that this situation will continue. In recent cases where lifeboats have been used in earnest, their occupants have been picked up by search and rescue services or the boats have reached shore in a relatively short space of time. This has led some to question whether the equipment that is required by SOLAS to be carried by survival craft is still necessary or appropriate, especially for vessels operating close to shore.
The Polar Code adopted in November 2014 has some special requirements for survival craft that include a requirement for each to have communication equipment and searchlights as well as a requirement for lifeboats to be fully or partially enclosed. At least one maker has produced a purpose-designed Polar liferaft.
SOLAS requires all lifeboats, liferafts and launching apparatus to be serviced at regular intervals. During the mid-2000s the IMO issued guidelines and intended to make mandatory requirements for all LSAs to be serviced and repaired only by OEMs. There was much opposition to this from independent servicing organisations who argued that their competence had been proved over time and that not all OEMs were still in existence. The debate subsided after it was agreed that independent service providers could continue to operate either by becoming approved by the OEMs or recognised by flag states.
Moving en masse
On most ships, including offshore vessels with contractor staff onboard, where total personnel numbers are measured in tens or very low hundreds, an evacuation in an emergency can be done quite rapidly using conventional lifeboats and liferafts but the same is not likely to be true for passenger vessels. Not only will there be many more persons to evacuate – maybe as many as 5,000 – but their mobility is likely to be less and with more people involved the potential for panic increases.
Since the 1990s, marine evacuation systems (MES) that make use of liferafts or platforms that are reached using either a slide or a chute have become standard equipment for passenger vessels. Regulations concerning MES are contained in both SOLAS and the LSA Code but ultimate approval to fit a system in place of required liferafts is the prerogative of the flag state. Any liferafts used in conjunction with a MES are subject to the requirements of the LSA Code, Chapter 4, section 4.1 and 4.2. Examination requirements are in accordance with SOLAS chapter III/20.8 and Chapter 6 of the LSA code; 6.2 covers MES specifically and in detail.
Because an MES is designed for evacuation only, it cannot be recovered and re-stowed as a lifeboat could be, nor is it possible for the system to be deployed for the purposes of passenger drills. This limitation is addressed in SOLAS chapter III/188.8.131.52 which says, “drills shall include exercising of the procedures required for deployment up to the point of actual deployment by the system party assigned to the MES.” Crew trained in using the systems are given instruction in assisting passengers when needed. However, there is little opportunity during operations to check and practice with the system because of the limitation mentioned.
All MES installations are required to be inspected annually and deployed in rotation at six yearly intervals. The conditions for deployment can vary according to flag state requirements and the six-year interval can be reduced. Some flag states have concerns over failed deployments and the matter is being reviewed on a continual basis, although it should be said that the issue of failed deployments appears to have faded in recent years.
An MES is usually housed at the embarkation station and activated by a crewmember. When activated, the liferaft or platform deploys along with the connecting slide or chute. The slides are inflatable structures to give some rigidity while the chutes may or may not have inflating elements incorporated into them. Although the chutes appear to be steeper than the slides – often hanging vertically – there is not a direct drop inside as the internal structure makes use of a helical slide or baffles to slow descent.
When an MES is in use, some of the liferaft crew will descend to the liferaft to supervise and one or more will be stationed at the evacuation deck to assist passengers board. Although the systems are capable of evacuating passengers much faster than conventional davit-launched liferafts, they can be daunting prospects for trepid passengers; chutes perhaps more so than slides. Since the first systems were developed, variations have been produced with mini versions designed for vessels with low embarkation decks.
Safer on board?
During the early years of the 21st century, some bold new ideas for ensuring passenger safety were formulated and discussed. Among these were proposals for parts of a ship’s superstructure to act as self-contained ships-within-a-ship that would float free as the mother vessel foundered.
Goal-based standards at the IMO and the risk-based approach of the EU’s Safedor project, as well as the IMO’s prescription that passengers should under most emergency circumstances affecting large passenger vessels remain protected in a safe area on board, may one day allow some of the more innovative to become reality but in practice designers have remained more conservative.
The safe return to port and safe area regulation appears to have killed off further development of the ship-within-a-ship concept. In 2006 MSC 82/12 agreed amendments to SOLAS (Chapter II-1and Chapter II-2, Regulations 21- 22) applicable to certain passenger ships (those of which the keels were laid on or after 1 July 2010, having a length of 120m or more, or having three or more main vertical zones). The safe area requirements stipulate that basic services with regard to sanitation, food, shelter and medical aid are to be available to ensure that the health of the passengers and crew is maintained as the ship proceeds to port.
The safe return to port requirements are not without their critics as many believe that a major incident would not permit a ship to return to port and evacuation into lifeboats will be inevitable. More recently, the advent of a new breed of expedition cruise ships has seen some raise other concerns, not least because many of these vessels, which will operate in remote areas, are being built to dimensions that exempt them from the safe return to port rules