Aug 212009
 
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Lifeboat, or Mandarina, from Usumacinta evacuation: IADC cautions on IMO solutions

IADC, the International Association Of Drilling Contractors, has issued warnings to its members regarding lifeboat safety in the wake of several incidents over the past year and guidance by the IMO.

SAYS IADC “Interest has been heightened due to the circulation of a dramatic video of a lifeboat incident, and an incident resulting in one fatality and injuries to six other personnel during a planned lifeboat drill on a MODU.”

The IMO is demanding the replacement of poorly design and unstable on-load release mechanisms and guidelines on how to evaluate them are scheduled to be discussed in February 2010.

IADC says: “this will remain a complex matter: It may not be cost effective to replace release mechanisms on older lifeboats and ergonomically compatible replacement mechanisms may not be available for all current hook arrangements. IADC believes the risks posed by most existing release mechanisms can, in the short term, be mitigated and cautions against taking  precipitous action to replace release mechanisms without comprehensively examining all issues related to existing life boat arrangements.”

Recently, the IMO has clarified the use of Fall Preventer Devices, FPDs, to enhance safety during drills. However, says the IADC: “It should be recognized that the use of FPDs introduces new risks and these need to be considered in both the design and operation of the FPDs.

“FPDs can not always be fitted, as there is not always a strong enough means of attachment; it depends on the hook arrangement. Generally, FPDs should not be attached to “hang off” or maintenance strap connections as they are not typically designed for the weight of the fully-loaded boat.

“The guidelines indicate that wires or chains should not be used as FPDs as they do not absorb shock loads. In considering synthetic strops or slings for FPDs, careful consideration should be given to the potential failure modes of the complete strop/sling assembly, as it is intended to be installed and used.”

On launching a lifeboat for a drill with or without crew aboard IADC says: “Most Administrations recognize the difficulties associated with safely launching and retrieving survival craft in the offshore environment, and do not demand that personnel be placed at risk in order to achieve compliance with SOLAS regulation III/19.3.3.3. Where a unit’s operating environment is such that compliance with SOLAS regulation III/19.3.3.3 cannot be safely assured, the Administration should be
contacted regarding dispensations or acceptable alternative arrangements.”

Also of concern is the size of lifeboat occupants, called ‘anthropomorphic compatibility’. Most SOLAS-approved lifeboats have been approved on the basis of an assumed occupant mass of 75 kg. The IMO has recently increased the assumed occupant mass for lifeboats on most new installations to 82.5 kg but IMO did not alter the seat width standard, which remains 430 mm when increasing the assumed
occupant mass.

A so-called “Gulf of Mexico standard” is being used by some that assumes an
occupant weight of about 95 kg with a corresponding seat width of some 530mm. This is also being addressed by coastal State authorities in the North Sea.

Differences between assumed occupant mass and actual mass affects the lifeboat in terms of crowding and stability, and may bring into question the adequacy of the davit, winch, and other weight bearing components.

Cautions IADC: “The adequacy of existing lifeboat arrangements should be assessed for anthropomorphic compatibility with the workforce in the MODU’s areas of operation.”

Another issue addressed is redundant lifeboat capacity. Separated and redundant lifeboat capacity, or alternatively, free-fall lifeboats, has been required for newer units in recognition of the potential for certain casualties to damage or render
inaccessible a unit’s lifeboats. Many older units may still be operating without the having the redundant lifeboat capacity now specified in the IMO MODU Code.

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Two lifeboats from Usumacinta. Top lifeboat was damaged in storm against a ship attempting rescue, bottom lifeboat capsized, upper structure damaged when it beached. Lifeboats lacked radios, transponders and other survival elements.

Says IADC: “A recent casualty highlighted the possibility that lifeboats on one side of a unit may be rendered inaccessible.”

Ageing lifeboats reach a point at which replacement becomes a more attractive option than performing major maintenance and repair. Like the average age of the MODU fleet, the average age of a lifeboat is over 25 years. The cost to completely refurbish a
lifeboat, not including replacement of the releasing mechanism, can be 50 percent or more of the cost of a new lifeboat. Even after refurbishment many lifeboats will not meet the latest SOLAS and LSA Code standards such as self-righting when fully flooded, four-point restraints, above water egress and entry points, and anthropomorphic compatibility.

”A formal ‘management of change’ process should be used where a replacement-in-kind of any lifesaving appliance component cannot be positively confirmed,” says IADC, “Any replacement component should satisfy the original design specification as to size, material, style, type, range, material and chemical properties, controls, operations and procedures. Approval by the flag-state administration or its recognized organization may be necessary.”

Of  particular concern in offshore emergencies is hydrogen sulphide, H2S, as, says the IADC, special consideration needs to be given to the means of escape for units operating in areas where there is the potential for the release of hydrogen sulphide gas. The issue was highlighted by the October 2007 Usumacinta incident in the Gulf of Mexico which cost 22 lives.

Evacuation in the presence of H2S will require personnel to use personal air tanks, however, in general, individual air tanks should not be taken into lifeboats because there is no provision for securing them: They can pose a missile hazard or adversely affect the boat’s stability.

The LSA Code does provide standards for lifeboats with self-contained air support systems. If such lifeboats are fitted, the 10 minute minimum air supply specified in the LSA Code should be examined in relation to a unit’s particular arrangements and anticipated operations. For example, an installed air system should be of sufficient capacity to allow occupants to transition between individual air tanks and lifeboat-supplied air as well as allow time for lowering the boat and moving to an area free
of hydrogen sulphide.

Training and competence. Each of the above referenced MSC circulars contains, or implies, an element of training. Personnel undertaking inspections, maintenance and adjustment of lifeboats, launching appliances and associated equipment should be fully trained and familiar with these duties, whether they are rig personnel, service company personnel, or equipment manufacturer employees.

The International Convention on Standards of Training, Certification and Watchkeeping, STCW, provides standards for proficiency in survival craft and rescue boats. While STCW is not directly applicable to many MODUs, IMO resolution A.891(21), “Recommendations on Training of Personnel on Mobile Offshore Units,” recommends that the STCW standards for proficiency in survival craft and rescue boats be applied to personnel with similar duties on all mobile offshore units, including MODUs.

Says IADC: “The STCW competency assessment is based upon generalized criteria and personnel should be provided with supplemental training with respect to the specific equipment which they will be assigned to operate. This training (and where applicable) proficiency certification is reinforced through regular participation in drills and exercises.”

Similarly, STCW and resolution A.891(21) address both vessel or unit specific ‘familiarization training’ and basic training in ‘personal survival techniques’ intended to provide personnel with the training necessary to cope with emergency situations specific to the unit on which they are serving. As with the training for personnel operating survival craft, the training for personnel who may need to rely on survival craft is reinforced through regular participation in appropriate drills and exercises.

The above training and drills should provide all personnel with realistic expectations regarding the conditions they may encounter during preparations for abandonment, within the survival craft itself, during recovery operations, and the need for discipline in each instance.

“Lack of appropriate training and  discipline can have tragic consequences” warns IADC.

Relevant IMO Materials:

http://www.imo.org/includes/blastDataOnly.asp/data_id%3D25943/1206-Rev-1.pdf
http://www.imo.org/includes/blastDataOnly.asp/data_id%3D22233/1277.pdf
http://www.imo.org/includes/blastDataOnly.asp/data_id%3D22234/1278.pdf
http://www.imo.org/includes/blastDataOnly.asp/data_id%3D25969/1326.pdf
http://www.imo.org/includes/blastDataOnly.asp/data_id%3D25970/1327.pdf

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