RESOLUTION MEPC.288(71)
(adopted on 7 July 2017)
2017
GUIDELINES FOR BALLAST WATER EXCHANGE (G6)
THE
MARINE ENVIRONMENT PROTECTION COMMITTEE,
RECALLING
Article 38(a) of the Convention on the International Maritime Organization
concerning the functions of the Marine Environment Protection Committee
conferred upon it by international conventions for the prevention and control
of marine pollution from ships,
RECALLING
ALSO that the International Conference on Ballast Water Management for Ships
held in February 2004 adopted the International Convention for the Control and
Management of Ships' Ballast Water and Sediments, 2004 (the Convention)
together with four Conference resolutions,
NOTING
that regulation A-2 of the Convention requires that discharge of ballast water
shall only be conducted through ballast water management in accordance with the
provisions of the Annex to the Convention,
NOTING
ALSO that regulation B-4 of the Annex to the Convention addresses the
conditions under which ballast water exchange should be conducted, taking into
account Guidelines developed by the Organization,
NOTING
FURTHER resolution MEPC.124(53)
by which the Committee adopted the Guidelines for ballast water exchange
(G6) and resolved to keep them under review,
HAVING
AGREED, at its seventieth session, to revise the Guidelines (G6) to incorporate
the ballast water reporting form set out in appendix 1 of the Guidelines for
the control and management of ships' ballast water to minimize the transfer of
harmful aquatic organisms and pathogens (resolution A.868(20)),
HAVING
CONSIDERED, at its seventy-first session, draft revised Guidelines for
ballast water exchange (G6),
1 ADOPTS the 2017 Guidelines
for ballast water exchange (G6) (the 2017 Guidelines (G6)), as set
out in the annex to this resolution;
2 INVITES Governments to apply the 2017
Guidelines (G6) as soon as possible, or when the Convention becomes applicable
to them;
3 AGREES to keep the 2017 Guidelines
(G6) under review in light of experience gained with their application;
4 REVOKES the Guidelines adopted by
resolution MEPC.124(53).
ANNEX
2017 GUIDELINES FOR BALLAST WATER EXCHANGE (G6)
1 INTRODUCTION
1.1 The purpose of
these Guidelines is to provide shipowners and operators with general guidance
on the development of ship specific procedures for conducting ballast water
exchange. Whenever possible shipowners and operators should enlist the
assistance of classification societies or qualified marine surveyors in
tailoring ballast exchange practices for various conditions of weather, cargo
and stability. The application of processes and procedures concerning ballast
water management are at the core of the solution to prevent, minimize and
ultimately eliminate the introduction of harmful aquatic organisms and
pathogens. Ballast water exchange offers a means, when used in conjunction with
good ballast water management practices, to assist in achieving this solution.
1.2 Ballast water
exchange introduces a number of safety issues, which affect both the ship and
its crew. These Guidelines are intended to provide guidance on the safety and
operational aspects of ballast water exchange at sea.
1.3 Given that there
are different types of ships which may be required to undertake ballast water
exchange at sea, it is impractical to provide specific guidelines for each ship
type. Shipowners are cautioned that they should consider the many variables
that apply to their ships. Some of these variables include type and size of
ship, ballast tank configurations and associated pumping systems, trading
routes and associated weather conditions, port State requirements and manning.
Application
1.4 The Guidelines
apply to all those involved with ballast water exchange, including shipowners
and operators, designers, classification societies and shipbuilders.
Operational procedures and guidance reflecting the issues raised in these
Guidelines should be reflected in the ship's ballast water management plan.
2 DEFINITIONS
For the purposes of these Guidelines, the definitions in the
International Convention for the Control and Management of Ships' Ballast Water
and Sediments (the Convention) apply and "ballast water tank" means
any tank, hold or space used for the carriage of ballast water.
3 RESPONSIBILITIES
3.1 Shipowners and
operators should ensure, prior to undertaking ballast water exchange, that all
the safety aspects associated with the ballast water exchange method or methods
used on board have been considered and that suitably trained personnel are on
board. A review of the safety aspects, the suitability of the exchange methods
being used and the aspects of crew training should be undertaken at regular
intervals.
3.2 The ballast water
management plan should include the duties of key shipboard control personnel
undertaking ballast water exchange at sea. Such personnel should be fully
conversant with the safety aspects of ballast water exchange and in particular
the method of exchange used on board their ship and the particular safety
aspects associated with the method used.
3.3 In accordance with
regulation B-4.4 of the Convention, if the master reasonably decides that to
perform ballast water exchange would threaten the safety or stability of the
ship, its crew or its passengers, because of adverse weather, the ship's
design, stress, equipment failure, or any other extraordinary condition, a ship
shall not be required to comply with regulations B-4.1 and B-4.2.
.1 When a ship does not
undertake ballast water exchange for the reasons stated above, the reasons
shall be entered in the ballast water record book.
.2 The port or coastal
State concerned may require that the discharge of ballast water must be in
accordance with procedures determined by them, taking into account the Guidelines
for additional measures including emergency situations (G13).
3.4 Where a port State
requires specific information regarding the management of ballast water on a
ship bound for a port, offshore terminal or anchorage area in that port State,
a completed ballast water reporting form as set out in the appendix may be
submitted prior to entry into that port State in a timeframe required by that port
State.
4 BALLAST WATER
EXCHANGE REQUIREMENTS
4.1 Exchange of ballast
water in deep ocean areas or open seas offers a means of limiting the
probability that harmful aquatic organisms and pathogens be transferred in
ships' ballast water.
4.2 Regulation D-1 of the Convention requires that:
.1 ships performing
ballast water exchange in accordance with this regulation shall do so with an
efficiency of at least 95% volumetric exchange of ballast water; and
.2 for ships exchanging
ballast water by the pumping-through method, pumping through three times the
volume of each ballast water tank shall be considered to meet the standard
described in paragraph 1. Pumping through less than three times the volume may
be accepted provided the ship can demonstrate that at least 95% volumetric
exchange is met.
4.3 There are three
methods of ballast water exchange which have been evaluated and accepted by the
Organization. The three methods are the sequential method, the flow-through
method and the dilution method. The flow-through method and the dilution method
are considered as "pump through" methods.
4.4 The three accepted methods can be described as follows:
.1 Sequential method
a process by which a ballast tank intended for the carriage of ballast water
is first emptied and then refilled with replacement ballast water to achieve at
least a 95% volumetric exchange.
.2 Flow-through
method a process by which replacement ballast water is pumped into a
ballast tank intended for the carriage of ballast water, allowing water to flow
through overflow or other arrangements.
.3 Dilution method
a process by which replacement ballast water is filled through the top of the
ballast tank intended for the carriage of ballast water with simultaneous discharge
from the bottom at the same flow rate and maintaining a constant level in the
tank throughout the ballast exchange operation.
5 SAFETY PRECAUTIONS
ASSOCIATED WITH BALLAST WATER EXCHANGE
5.1 Three methods of
carrying out ballast water exchange at sea have been identified as acceptable
by the Organization. Each has particular safety aspects associated with it that
should be considered when selecting the method(s) to be used on a particular
ship.
5.2 When identifying
the ballast water exchange method(s) for the first time for a particular ship,
an evaluation should be made which should include:
.1 the safety margins
for stability and strength contained in allowable seagoing conditions, as
specified in the approved trim and stability booklet and the loading manual
relevant to individual types of ships. Account should also be taken of the
loading conditions and the envisaged ballast water exchange method or methods
to be used;
.2 the ballast pumping
and piping system taking account of the number of ballast pumps and their
capacities, size and arrangements of ballast water tanks; and
.3 the availability and
capacity of tank vents and overflow arrangements, for the flow through method,
the availability and capacity of tank overflow points, prevention of under and
over pressurization of the ballast tanks.
5.3 Particular account should be taken of the following:
.1 stability which is
to be maintained at all times and not less than those values recommended by the
Organization or required by the Administration;
.2 longitudinal stress,
and where applicable torsional stress values, not to exceed permitted values
with regard to prevailing sea conditions;
.3 exchange of ballast
in tanks where significant structural loads may be generated by sloshing action
in the partially filled tank to be carried out in favourable sea and swell
conditions such that the risk of structural damage is minimized;
.4 wave-induced hull
vibrations when carrying out ballast water exchange;
.5 limitations of the
available methods of ballast water exchange in respect of sea and weather
conditions;
.6 forward and aft
draughts and trim, with particular reference to bridge visibility, slamming,
propeller immersion and minimum forward draft; and
.7 additional workloads
on the master and crew.
5.4 Having undertaken
an evaluation for a particular ship and the exchange method or methods to be
used, the ship should be provided with procedures, advice and information
appropriate to the exchange method(s) identified and ship type in the ballast
water management plan. The procedures, advice and information in the ballast
water management plan may include but are not limited to the following:
.1 avoidance of over
and under-pressurization of ballast tanks;
.2 free surface effects
on stability and sloshing loads in tanks that may be slack at any one time;
.3 maintain adequate
intact stability in accordance with an approved trim and stability booklet;
.4 permissible seagoing
strength limits of shear forces and bending moments in accordance with an
approved loading manual;
.5 torsional forces;
.6 forward and aft
draughts and trim, with particular reference to bridge visibility, propeller
immersion and minimum forward draft;
.7 wave-induced hull vibrations
when performing ballast water exchange;
.8 watertight and
weather-tight closures (e.g. manholes) which may have to be opened during
ballast exchange must be re-secured;
.9 maximum pumping/flow
rates to ensure the tank is not subjected to a pressure greater than that for
which it has been designed;
.10 internal transfers of
ballast;
.11 admissible weather
conditions;
.12 weather routeing in
areas seasonably affected by cyclones, typhoons, hurricanes, or heavy icing
conditions;
.13 documented records of
ballasting and/or de-ballasting and/or internal transfers of ballast;
.14 contingency
procedures for situations which may affect ballast water exchange at sea,
including deteriorating weather conditions, pump failure and loss of power;
.15 time to complete the
ballast water exchange for each tank or an appropriate sequence thereof;
.16 continual monitoring
of the ballast water operation; monitoring should include pumps, levels in
tanks, line and pump pressures, stability and stresses;
.17 a list of
circumstances in which ballast water exchange should not be undertaken. These
circumstances may result from critical situations of an exceptional nature or
force majeure due to stress of weather, known equipment failures or defects, or
any other circumstances in which human life or safety of the ship is
threatened;
.18 ballast water
exchange at sea should be avoided in freezing weather conditions. However, when
it is deemed absolutely necessary, particular attention should be paid to the
hazards associated with the freezing of overboard discharge arrangements, air
pipes, ballast system valves together with their means of control, and the
build-up of ice on deck; and
.19 personnel safety,
including precautions which may be required when personnel are required to work
on deck at night, in heavy weather, when ballast water overflows the deck, and
in freezing conditions. These concerns may be related to the risks to the
personnel of falling and injury, due to the slippery wet surface of the deck
plate, when water is overflowing on deck, and to the direct contact with the
ballast water, in terms of occupational health and safety.
5.5 During ballast
water exchange sequences there may be times when, for a transitory period, one
or more of the following criteria cannot be fully met or are found to be
difficult to maintain:
.1 bridge visibility
standards (SOLAS regulation V/22);
.2 propeller immersion;
and
.3 minimum draft
forward.
5.6 As the choice of
acceptable ballast water exchange sequences is limited for most ships, it is
not always practicable to dismiss from consideration those sequences where
transitory non-compliance may occur. The practical alternative would be to
accept such sequences provided an appropriate note is placed in the ballast
water management plan to alert the ship's master. The note would advise the
master of the nature of the transitory non-compliance, that additional planning
may be required and that adequate precautions need to be taken when using such sequences.
5.7 In planning a
ballast water exchange operation that includes sequences which involve periods
when the criteria for propeller immersion, minimum draft and/or trim and bridge
visibility cannot be met, the master should assess:
.1 the duration(s) and
time(s) during the operation that any of the criteria will not be met;
.2 the effect(s) on the
navigational and manoeuvring capabilities of the ship; and
.3 the time to complete
the operation.
5.8 A decision to proceed with the operation should only be taken
when it is anticipated that:
.1 the ship will be in
open water;
.2 the traffic density
will be low;
.3 an enhanced
navigational watch will be maintained including if necessary an additional look
out forward with adequate communications with the navigation bridge;
.4 the manoeuvrability
of the vessel will not be unduly impaired by the draft and trim and or
propeller immersion during the transitory period; and
.5 the general weather
and sea-state conditions will be suitable and unlikely to deteriorate.
5.9 On oil tankers,
segregated ballast and clean ballast may be discharged below the water line at
sea by pumps if the ballast water exchange is performed under the provisions of
regulation D-1.1 of the Convention, provided that the surface of the ballast
water has been examined either visually or by other means immediately before
the discharge to ensure that no contamination with oil has taken place.
6 CREW TRAINING AND
FAMILIARIZATION
6.1 Appropriate
training for ships' masters and crews should include instructions on the safety
issues associated with ballast water exchange based upon the information
contained in these Guidelines. Instruction should be provided on the ships'
ballast water management plan including the completion of required records.
6.2 Ships' officers and
crew engaged in ballast water exchange at sea should be trained in and be
familiar with the following as appropriate:
.1 the ship's ballast
pumping and piping arrangements, positions of associated air and sounding
pipes, positions of all compartment and tank suctions and pipelines connecting
them to ship's ballast pumps and, in the case of use of the flow through method
of ballast water exchange, the openings used for release of water from the top
of the tank together with overboard discharge arrangements;
.2 the method of
ensuring that sounding pipes are clear, and that air pipes and their non-return
devices are in good order;
.3 the different times
required to undertake the various ballast water exchange operations including
the time to complete individual tanks;
.4 the method(s) in use
for ballast water exchange at sea if applicable with particular reference to
required safety precautions; and
.5 the need to
continually monitor ballast water exchange operations.
7 FUTURE
CONSIDERATIONS IN RELATION TO BALLAST WATER EXCHANGE
These Guidelines may be revised and updated in the light of
possible technical evolutions with the ballast water exchange methods and of
new ballast water management options.
APPENDIX
EXAMPLE
BALLAST WATER REPORTING FORM