The application of THESIS Bow-Ties in marine ... - ABS Consulting

OPERATIONS REGULATIONS
the Clipper fleet over the next
four years will all be built to
comply with the new rules.
With only chemical carriers in
its fleet, Odjfell too doesn't have
many concerns with the new
rules. Most of its ships have full
double hull, while all have double
bottom. "But one issue may be
the fleet capacity with double
skin (full double hull) for the
older ships," says Jan D Lorentz,
Odfjell's senior vice president,
quality management.
As such, Odfjell has chosen to
convert one ship series to full
double hull in order to meet the
revision of the Marpol Annex II
regulation, which requires
enhanced hull protection for a
number of bulk liquid cargoes.
"Among the products affected
we find, for instance, vegetable
oils that must be carried in
tankers with double hull,
corresponding to recent changes
in the requirements to carry
mineral oil products. Accordingly,
a number of tankers will become
commercially less suitable" says
Odfjell's Helge Olsen, senior vice
president, ship management.
Because Odfjell's KSEC class,
built in Korea between 1986 and
1988, has no protection of its
wing tanks, the Norwegian
shipowner would be facing a
reduction in the range of products
allowed to be carried in these
ships. However, as the vessels
otherwise have a technical
standard that should allow trading
for many years, Odfjell assessed
the feasibility of upgrading to
comply with the new rules.
Evaluation of the technical
feasibility and economics of
upgrading the five sister vessels -
Bow Puma, Bow Panther, Bow
Lion, Bow Leopard and Bow
Cheetah - began in August 2005.
The project involved a
multidisciplinary team, including
internal and external specialists,
as well as required participation
by the classification society DNV
to review and approve the design.
The initial engineering design
was approved in February this
year, and Chinese shipyard
Nantong won the order to carry
out the conversion work. The
upgrading of each vessel will
involve the removal of the existing
shell plating in way of the cargo
section and replacing it with
blocks of prefabricated steelwork
to create double skin ballast tanks
on each side. The width of the
new double sides will exceed
requirements to facilitate
operations and maintenance, and
the increased scantling will
enhance the vessels' strength.
Each vessel is expected to
spend around 50 days at the yard
for this combined upgrading and
general docking work. Within this
tight schedule, the yard will also
blast and repaint the vessels'
entire hull, including necessary
restoration of cargo tank coatings
that is affected by the conversion.
All in all, it is envisaged the
new ruling shouldn't greatly affect
the sector. The UK MCA, for
instance, believed that if there
were concerns, objections would
have been noted at IMO. But
"shipowners or the International
Chamber of Shipping haven't
approached us about any
problems," said the MCA's David
Macrae. However, he did say that
indications suggest that a number
of Ship Type 1 vessels will
convert to Ship Type II or III, but
it won't be known whether there is
an over- or under-supply of oil
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tanker tonnage until it happens.
The application of THESIS Bow-Ties in marine safety
management*
In an industry which is
moving further towards
demonstrable and
accountable risk
management, the
THESIS Bow-Tie tool is
gaining greater
acceptance. The
methodology is proven
by track record in the
offshore, process and
security risk industries
and the tool
continuously adapted to
suite the need.
THESIS (The Health,
Environment, Safety Information
System) is a software tool that
can effectively demonstrate how
a facility's Safety Management
System can be implemented. It
assists companies/operators in the
analysis and management of the
hazards and risks to which their
business is exposed, and
graphically displays and
illustrates the relationship
between hazards, controls, risk
reduction measures and a
business's HSSE activities.
Regulators and stakeholders
across the world are progressively
expecting more information to be
included in the documentation
used to demonstrate that an
operation/asset has an effective
safety management system. This
is becoming increasingly evident
in the marine industry in the form
of equivalent safety cases which
aim to confirm that:
• all credible hazards have been
identified;
• appropriate standards have
been set and met;
• adequate safety features are in
place;
• all significant assumptions
have been identified, verified
and validated;
• all instructions, limits and
conditions required to
maintain operations within
specified margins for safety
have been met.
In addressing these aims, a
number of documents would be
traditionally generated. These
documents inherently become
increasingly complicated with the
onus on fulfilling the requirements
and the explanation of all the
interactions between these
documents becomes more difficult
ELEMENTS
Policy & Strategic Objectives
Organisation, Responsibilities,
Resources, Standards & Docs.
Hazard & Effects Management
Process
Planning & Procedures
Implementation & Monitoring
Audit
Review
to explain to the workforce,
regulator and stakeholders.
This can, however, be made
much easier with the help of an
interactive graphical
representation. This graphical
REQUIREMENTS
• Safety Policy
• Strategic Objectives & Targets
• Organisational Structure &
Responsibilities
• Management Representatives
• Resources
• Competence
• Contractors
• Communication
• Documentation & it’s Control
• Identification of Hazards &
Effects
• Risk Evaluation
• Recording of Hazards & Effects
• Objectives of Performance
Criteria
• Asset Integrity
• Procedures & Work Instructions
• Management of Change
• Contingency & Emergency
Planning
• Monitoring
• Records
• Non-Compliance & Corrective
Action
• Incident Reporting & Follow-Up
• Internal Audit
• Independent Audits
• Management Review
Figure 1: Typical elements and requirements of a facility's risk
management system
September 2006 • TANKEROperator 35

OPERATIONS
Escalation
factors
Control of
escalation
factor
Control of
escalation
factor
Escalation
factors
Failure of p/v
arrangement
Threat
Regular maintenance. Pre-operational
inspections, certification and company
form E116, E490.
Pressure indicator: Common IGS line,
CCR. Monitoring of repeater in bridge
Locking arrangements
P/V breaker. Common IGS line
Consequences
Failure of repeater of
pressure indicator
Escalation Factor
Hazard
Threat
that could
release
hazard
Barriers to
prevent
threat
Recovery
preparedness
measures
Top event Consequences
Failure of locking
arrangements
Escalation Factor
Maintenance of locking arrangements
Failure or freezing of p/v
breaker
H-01.S01 Hydrocarbons
Loc.: Sea
TE: Loss of
containment cargo
tanks (Sea)
Discharge at sea.
Pollution
Consequence
Hull flooding. Potential for
loss of stability
Consequence
Escalation Factor
Fire/explosion
Consequences
Monthly inspection program (E116,
E480). Precautions during cold
weather.
Consequence
Personnel injury/fatality
Corrosion
Consequence
Threat
Classification society surveys will
monitor wastage and remedial actions
taken if limits exceeded. Strength
analysis (CAP) as per current new
building criteria.
Coating protection on ballast and
cargo tanks, cathodic protection to
ballast tanks
Daily inspection and maintenance
program (E-116)
Activities & tasks
Thermal expansion of
cargo
Threat
Procedures to allow for cargo
expansion: tanks to be filled 98% of
their capacity.
High and high-high level alarms
Pressure/vacuum relief valve
p/v breaker: Common IGS line
= HSE-critical task
Figure 2: A typical bow-tie display
Figure 3: A partially expanded THESIS Tow Tie for a Loss of Cargo
Containment
representation has become to be
known as the THESIS bow-tie
methodology. By building in a
risk matrix, effectiveness ranking
and performance data for the
control measures then the bow tie
methodology also becomes a semiquantitative
risk assessment tool.
THESIS Bow-Tie
Methodology
THESIS can be used to
demonstrate how effective a
marine facility's safety
management system is performing
and also to complete gap analyses.
A typical management system is a
quality management system for
managing risks within a company,
to assure the protection of the
company's people, assets,
reputation and for protection of
the environment the company
operates within. A typical safety
management system would
comprise of the elements shown in
Figure 1, previous page.
The bow tie can be used to
demonstrate how the pertinent
safety management system
element requirements are met
with respect to the control and
management of hazards and risks.
Bow-ties depict the relationship
between hazards, threats, barriers,
escalation factors, controls,
consequences, recovery
preparedness measures and
critical tasks (Figure 2, above).
This has been an area of fault or
weakness in many organisations -
using this method can help to
display all the interactions and
links that are often found to be
loosely related over a number of
various documents.
Essentially a bow-tie is a
combination of the traditionally
used fault and event trees,
whereby the fault tree constitutes
the left hand side of a bow-tie and
the event tree the right hand side.
What a bow-tie presents in
addition however, are the
'barriers' in place that prevent
'threats' from releasing a hazard
and 'recovery preparedness
measures' that reduce the severity
of the hazard consequences.
Critical Tasks
Once the threats, consequences,
escalation factors and all controls
have been identified, supporting
tasks to ensure that the integrity
of each barrier, control and
recovery preparedness measure is
maintained need to be assigned.
These are termed Critical Tasks,
and are required to be performed,
undertaken or executed by
responsible and competent
persons. Such tasks could
include:
• Design Tasks;
• Inspection and Maintenance
Tasks;
• Operational Tasks; and
• Administrative Tasks.
Assigning Personnel to
Critical Tasks
Once the critical tasks are defined,
personnel are assigned the
responsibility for the execution of
the tasks. Such persons are
identified from the organisation at
the time of undertaking the work
and should remain, at the least, at
a supervisory level. The
procedures and standards
necessary to support that task are
captured at the same time.
The advantage of adopting the
THESIS approach is that it is an
extremely powerful representation
of the hazard analysis and risk
management processes that is
readily understood at all levels in
an organisation; bow-ties can be
used in the boardroom as well as
in a tool box talk.
Case Example
Figure 3 illustrates a
representation of one of the many
hazards that faces a cargo
containing vessel at sea.
The left hand side of the bowtie
shows a number of possible
threats that could potentially
release hazardous cargo and thus
produce the top event. Some
engineered and procedural
barriers have been put in place
here to illustrate typical
protection measures that would
prevent the threat from releasing
the hazard. Escalation factors
have been expanded in Figure 3
to show the controls put in place
to manage the escalation factor.
The right hand side illustrates
the consequential outcomes of the
top event. Recovery measures
are not illustrated further.
It is possible within the 'case
file' to also:-
• capture the integrity of
barriers,
• capture system shortfalls and
set remedial action plans
• define the tasks and personnel
for managing barriers and
indeed assign them
• set task frequencies
• assign documentation and
standards
• populate a risk matrix and
illustrate the risk profile
• produce reports for use in
supporting documentation eg.
safety manual, audit, training,
appraisal etc.
THESIS Summary
THESIS is an application,
originally developed by Shell and
now jointly with ABS Consulting.
It has been developed based on the
Bow-Tie concept to visually
display how hazards are controlled
and how the risk associated with
them is reduced to As Low As
Reasonably Practical (ALARP). It
documents the provenance of
information and the reference
sources from which the
information is obtained, i.e. it is an
ideal audit tool.
It is an extremely flexible tool
and simple tool whose application
extends from safety, health and
environment risk into any aspect
of business exposed to hazards
and risks. It is frequently used to
build management systems from
concept as well as capture and
refine those that already exist.
* By James Phipps, principal
risk consultant, ABS Consulting
Ltd (Warrington, UK)
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TANKEROperator • September 2006