Page 40 - Practical Design Ships and Floating Structures

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be retrofitted on existing crude oil tankers, and redundant steering gear facilities were required on all
new and existing tankers.
With the new 1978 protocols to MARPOL and SOLAS, it was hoped that these new regulations would
mark an end to regulatory driven changes. It was hoped that by tightening the standards on the design
of the tanker structure, the seaways would be made safer and significantly less polluted. Fortunately it
did for a while, lasting through most of the decade of the 80’s

But that peace came to an end in March of 1989, when the oil tanker EXXON VALDEZ, which met
the requirements of the 1978 protocols to MARPOL, ran aground in Prince William Sound, Alaska.
The regulatory breather was over and the call for stricter regulations started over again.

3 THE U.S. OIL POLLUTION ACT OF 1990

As result of the VALDEZ oil spill, the U.S. Congress passed the Oil Pollution Act of 1990. OPA-90,
as it is commonly referred, set double hull requirements for all new tankers operating in U.S. waters
and mandated a phase out of existing single hull tankers. In its final impact, OPA-90 also prompted
the 1992 amendments to MARPOL mandating double hull tankers or equivalent designs throughout
the world.

Unfortunately the decade of the 90’s had not seen much relief in regulatory pressures. There was the
grounding of the oil tanker BRAER offthe Shetland Islands, and the grounding of the oil tanker SEA
EMPRESS off the coast of Wales.

4 NEW EMPHASIS ON THE HUMAN ELEMENT

Following OPA-90 and the requirement for double hull tankers, the regulatory pressure had shifted to a
new emphasis on the human element in the marine safety equation. Within IMO, two initiatives were
developed. One was the International Safety Management (ISM) Code, which defined a management
system approach for the management and operation of all vessels. The other was major revisions to
the Convention on Standards of Training, Certification and Watchkeeping (STCW) of Seafarers.
While this has very little to do with technical design change in a direct sense, greater attention was
being given to the human aspects of marine safety, since it is known that about 80% of accidents is due
to human error.

5 RECENT CASUALTIES

Unfortunately tanker disasters resulting in oil pollution still make the news today, From December
1999 through January 1 2001 there were five major casualties that occurred in European waters. In
December 1999, the 25 year old 37,000 dwt single hull tanker ERIKA broke in half and sank 40 miles
off the coast of Brittany France, spilling over 10,000 tons of heavy fuel oil, resulting in the pollution of
the coastline. Other recent tanker casualties were:

IEVOLI SUN - an 11 year old chemical tanker that sunk due to internal flooding, likely due to
structural failure.

CASTOR - a 23 year old product carrier that had a 20 meter crack develop across its deck.
Fortunately it did not sink.