A number of measures could and should be taken to avoid discharges
of oil from shipping (oil tankers and other vessels) and from
platforms for offshore
oil extraction. Measures to reduce the risk of accidents
involving tankers, and measures to reduce operational discharges
from all kinds of commercial vessels, include the following:
SHIP'S
DESIGN
Requirements for double hulls or double bottoms are being
introduced. In 1992, the MARPOL Convention was amended to
make it mandatory for tankers of 5,000 dwt and more (ships
ordered after 6 July 1993) to be fitted with double hulls,
or an alternative design approved by IMO (Regulation 13F in
Annex I of MARPOL 73/78). The requirement for double
hulls that applies to new tankers has also been applied to
existing ships under a programme that began in 1995 (Regulation
13G in Annex I of MARPOL 73/78). All tankers have to
be converted (or taken out of service) when they reach a certain
age (up to 30 years old). This measure is being phased in
over a number of years because shipyard capacity is limited
and it would not be possible to convert all single hulled
tankers to double hulls without causing immense disruption
to world trade and industry. There are also concerns about
building vessels too fast and compromising design standards.
An additional possible measure is to limit
the size of individual tanks within ships so that spills that
occur at least are smaller.
Single hull is a ship construction term. In tankers
with single hulls, oil in the cargo tanks is separated from
the seawater only by a bottom and a side plate. Should this
plate be damaged as a result of a collision or stranding,
the contents of the cargo tanks risks spilling into the sea.
An effective way of avoiding the risk is to surround the cargo
tanks with a second internal plate which is at a sufficient
distance from the external plate (generally 1.5-2 metres).
This design, known as a double hull, safeguards cargo
tanks from damage and thus reduces the risk of oil pollution.
The double hull construction incorporates both double bottoms
and double sides. An alternative solution is to have ships
with double sides (double hull along the sides of the
ship, an added side-shell plating structure fitted within
the ship while the bottom of the ship has a single plate,
a single bottom. This means that the cargo tanks
are separated from the seawater only by a bottom plate.
Double bottom, on the other hand, is a ship construction
term referring to two separate but continuous and water-tight
plating structures along some length and width of a ship's
bottom.
The U.S. has already banned single hull-vessels in their waters
and has stronger liability legislation in their Oil Polllution
Act.
Shortly after the Erika accident, the EU Commission
presented a number of proposals to help prevent such accidents
occurring again. One measure was a proposed Regulation on
the phasing out of single-hull oil tankers. This Regulation
was adopted on 20 February 2002, and applies from 1 September
2002. This measure was also agreed at the international level
when the IMO adopted a revision of its Regulation 13G of Annex
I to MARPOL 73/78 in April 2001. In 2002, after the Prestige
accident, it became clear that the international and previously
agreed EU schemes were not sufficiently ambitious. The Commission
announced a number of measures to minimise the risk of future
accidents involving ships such as Erika and Prestige.
The Transport Council in 2002, furthermore called for
an acceleration of the calendar for phasing-out of single-hull
tankers, for applying the Condition Assessment Scheme from
15 years of age, as well as the conclusion of administrative
agreements by Member States in view of refusing single hull
oil tankers carrying the heaviest grades of oil into their
ports, terminals and anchorage areas.
MAINTENANCE
& SHIP OWNER RESPONSIBILITY
Ship owners must ensure a high standard of maintenance. No
matter how well a ship is designed, built and equipped
unless it is properly maintained, it will sooner or later
become a maritime safety risk. The responsibility for regular
and good maintenance always rests with the ship owner. It
is also worth remembering that also double-hulls have their
own inherent problems. Many predict that in a few years time
there will be massive oil spills from double-hull tankers
as the maintenance of a double-hull is more difficult than
a single-hull, and there is also a problem with gas build
up between the two hulls. This will make regular inspections
of the vessels even more important.
COMPETENT
CREW
Furthermore, it is the responsibility of the ship owner to
recruite crews that are competent and experienced. The crews
should also be continuously trained. Many accidents are due
to the human factor, and unless the crew members do their
job right it does not really matter how well equipped the
ship is.
NAVIGATIONAL
AIDS AND ON BOARD EQUIPMENT
Better navigational equipment for example, electronic
charting is needed. All ships must have radar systems
to improve navigation (large ships must have two systems that
operate independently). In busy shipping corridors, traffic
separation schemes and vessel traffic control are required
to reduce the risk of a collision. In some areas, mandatory
pilotage should be introduced.
High-standard fire-fighting equipment must be available and
strict fire safety regulations apply on board.
Monitoring and control equipment should be installed on ships
so that discharged oil-water mixtures can be traced back to
the ship that was carrying the oil.
SURVEILLANCE
The purposes of surveillance is to function as a deterrent
from discharging ship-generated wastes altogether, as a means
of detection of discharges already made, and as a tool to
combat, as effectively as possible the spills that have been
detected. Airborne surveillance which increases the ship's
risk of being caught in the process of making illegal discharges
can be an effective measure to prevent discharges and thus
reduce marine pollution from shipping. In the future, airborne
surveillance on a regional scale should be introduced in more
areas, particularly in the MARPOL Special Areas (as is already
the case in the Northeast Atlantic and the Baltic Sea).
INSPECTIONS
Frequent inspection of ships, particularly older ones, are
imperative. Since 1995 all tankers and bulk carriers aged
five years and over have been subject to a specially enhanced
inspection programme which is intended to ensure that any
deficiencies such as corrosion or wear and tear resulting
from age or neglect are detected. Guidelines on enhanced
surveys on tankers and bulk carriers are contained in Assembly
resolution A. 744 (18), adopted in November 1993. Inspections
are coordinated on a regional scale through Memoranda of Understanding
on Port State Control (MoUs).
RECEPTION
FACILITIES
Better facilities are needed in ports for ships to leave their
oily liquid waste and solid oily waste. In MARPOL Special
Areas, such port reception facilities are required. However,
in order to further reduce marine oil pollution from shipping
such facilities should be made universally available in all
ports where oil and oily wastes are handled. These facilities
should, preferably, be made available at no extra cost, the
so-called no special fee system presently in use in the Baltic
Sea region.
CARGO
OWNER AND OIL CONSUMER RESPONSIBILITY
Finally, the responsibility for upholding safe sea transports
of oil products rests also with the cargo owners and the end
users, the consumers of the products. Cargo owners should
not use sub-standard vessels, but should be prepared to pay
for high-quality shipping. Ultimately, the additional costs
for choosing to charter safe and well maintained ships will
(marginally) affect the price of the products, but it is a
small price to pay as a means to prevent as far as possible
the pollution of the coastal and marine environment by oils.
|