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Part 4: Risk Management in
Construction


Construction Health & Safety Management


Simon Smith (University of Edinburgh)

& Philip Matyear (Balfour Beatty)

Introduction


We have looked H&S legislation


It must be remembered that legislation alone will not protect


it is
merely the

rules



We have considered the behavioural and cultural aspects of H&S
Management


We have looked at practical aspects of health & safety on
construction sites


We have considered specific areas where hazards occur


This lecture will consider


how H&S management is implemented at a site level


the wider concept of engineering risk management

Health & Safety Hierarchy


H&S Legislation

H&S File

Method Statement

Operation Plan

Risk

Assessment

General site

safety

management

Fundamental

topic: covered in

greater

depth

Health & Safety Legislation



As covered
Part 4


For example:



The Health & Safety at Work
etc

Act 1974


The Management of Health and Safety at Work Regulations
1999


The Provision and Use of Work Equipment Regulations 1998



The Manual Handling Operations Regulations 1992



The Construction (Head Protection) Regulations 1989


Personal Protective Equipment at Work Regulations 1992


Control of Substances Hazardous to Health Regulations 2002


Construction (Design and Management) Regulations
2007

Health & Safety File



To recap:


contains all H&S information about the
project for those that follow (i.e. clients &
users)


should contain information about the
design & construction of every structure
& element of the project


responsibility lies with the CDM Co
-
ordinator who must

»
keep it up to date

»
deliver to client at end of project

The Method Statement


A Method Statement defines the scope of the work
to be performed in producing a significant section
or phase of the project


It is also produced as part of the
Project Quality
Plan


It is a statement about the desired level of quality


As a definition of the work involved it allows
assessments of the risks involved to be made


Once prepared it should be passed to every person
involved in that part of the project


whatever
capacity they may have

Method Statements


areas covered


A method statement is a large document
and therefore cannot be prepared for all
activities


Work activities are therefore split into
areas


usually geographic but also process
areas


The project manager is responsible for
determining what method statements are
required


he must find the right balance:


too broad a scope and detail will be lost


too narrow and the volume of paperwork will
dominate

Method Statements


examples


On a road project we may have the
following method statements:


One for each major structure (e.g. bridges)


One for a group of minor structures (e.g.
culverts)


Earthworks


Fencing


Site clearance


Drainage


Road surfacing


Traffic management


Safety fencing


Any other specialist subcontractor operations


Content of a method statement


The

operations

concerned


A

risk

assessment

of

the

operations


A

listing

of

key

drawings


The

direction

and

sequence

of

work


The

types

of

resources

to

be

used


A

basic

layout

or

sketch


Delegated

responsibility

for

the

work


Any other specific aspects of the work


Operation Plans



The next level in the H&S hierarchy


It is prepared for each discrete
activity of work


There may be a number of operation
plans for an area of work already
covered by a method statement


The operation plan is usually drawn up
by the site engineer looking after the
work


A
pro
-
form

is usually used

Operation Plans


pro
-
forma

Activity No.
Activity Description
OP Ref
N.B. The activity number and location should be included on all allocation sheets
Material Requirements / Sequence of Work
Sequence of Work
Material Description
Quantity
Sketch Ref.
Inspection and Test Plan Ref.
Required Output
Remarks
(e.g. access etc.)
Plant/Lab
Risk Assessment
Hazard
Risk
Control Measures Required
Permits Required (Y/N)
Permit to Dig
Permit to Enter
Other
Permit to Pump
Hot Work Permit
(Specify)
Permit to Work
Permit to Load
Prepared By
Approved By
Date
Date
Ensure any applicable permits and sketches are appended to this sheet
Sequence of Work & Resources
Operation Plan
Principal Hazards
Rating (H/M/L)
Opportunity
Persons Affected
Risk Assessments



Risk


is a large part of any project


financial, technical & safety risk


It is just one stage in the overall
risk
management

strategy prepared for
every project


We shall look at the subject in greater
depth in a moment


Each method statement will have
detailed risk assessments:

Risk assessment only useful if the info in it
is well considered...

Risk Management


Risks are ever present


The management of risk is an area of
significant expansion over the last decade.


Within the construction and process
industries the consequences of an accident
can be significant (
e.g.Piper

Alpha)


Detailed management of risks are routinely
carried out, conducted at all stages of a
project life cycle


We will look at:


Define risk concepts


Introduce the Risk Management
Procedure

Engineering: Small Risks

Large Physical Hazards
-

Piper Alpha
(before & after)

Large Consequences: Hatfield, Ladbroke Grove,
Potters Bar & Greyrigg Rail Accidents

Hatfield,

17 October 2000,

4 killed

Ladbroke Grove,

5 October 1999,

31 killed

Grayrigg,

23 February 2007,

1 killed

Potters Bar,

10 May 2002,

7 killed

Some Definitions

Harm


Physical injury or damage to health,
property or the environment”

BS8444: Part 3: 1996

»
In all aspects of project management, we
want to minimise, if not eliminate any kind of
harm

»
Harm may be, for example:


Employee injury or death


Financial effects


Environmental accident


Definitions
cont.

Hazard

A source of potential harm or a situation with potential
for harm in terms of human injury, damage to property,
damage to the environment, or combination thereof


In project management terms, we need to
control financial hazards as well as physical
ones


Examples may be:

»
Falls from heights

»
Collapse of excavations

»
Dropped objects

»
Poor environmental management

»
Abnormal inflation

»
Abnormal weather conditions

Non
-
physical hazards


Inflation


Supplier changes


Supplier collapses


Reduction in supplies


Cultural
misunderstandings


Corruption


Interest rate changes


Market condition
changes


Changes in labour
supply


Skills shortage


Design changes


Changes in
legislation


Security threats


Political
changes/instability


Demand changes


Public opinion







Definitions
cont.

Risk

The combination of the probability of an
abnormal event or failure and the
consequence(s) of that event or failure to a
system’s operators, users or its environment


Risk
always
involves two aspects:

»
Probability of a hazard taking place, and

»
The severity of the harm that occurs


Low probability, high severity = high risk


High probability, low severity = intermediate risk


Low probability, low severity = low risk

Definitions
cont.

Risk Management

The systematic application of management
policies, procedures and practises to the
tasks of identifying, analysing, evaluating,
responding and monitoring risk

»
Five stages:

Baker, Ponniah, Smith, 1999

Survey of Risk Management in Major UK Companies,

Journal of Professional Issues in Engineering Education & Practice,

Hazard Identification

Hazard Identification


The stage where all potential hazards in a project
are identified


To me the most important part of
any

risk
management process


Because non
-
identified hazards cannot have their
risk assessed


“There are known knowns. These are things we
know that we know. There are known
unknowns. That is to say, there are things that
we now know we don’t know. But there are also
unknown unknowns. These are things we do not
know we don’t know”


Donald Rumsfeld, 12 Feb 2002

(relating to the increasingly unstable situation in post
-
invasion Afghanistan

Hazard Identification


Possible methods of identification


Individual Consultation

»
interviews with project personnel

»
lengthy & time consuming


Group discussions

»
formal brainstorming

»
requires motivation & teamwork


HAZOP

»
HAZ
ard and
OP
erability studies

»
Formal questioning of processes, e.g design

Risk Estimation


Potential hazards have been identified


Now need to assess:


Probability of occurrence


Severity if occurs


Can be done in two main ways:


Qualitatively

»
in a linguistic manner

»
usually done first; high probability/severity
cases then may be examined:


Quantitatively

»
in a numerical manner

Risk Estimation
cont

Qualitative Techniques


Fuzzy set analysis

»
Understands that likelihood and consequences
may not be definite, but rather will belong to
a ‘fuzzy set’ which has degrees of
membership

»
expresses the outcome in readily understood
language terms

»
For example


‘very likely risk with severe
impact’

Risk Estimation
cont

Qualitative Techniques


Interviewing and Brainstorming

»
is an extension of two of the techniques
employed in the identification stage.


Personal and Corporate Experience

»
if it exists should be exploited.


Judgment

»
We are all professionals and able to form valid
judgements

Risk Estimation
cont

Quantitative Techniques


Expected Monetary Value (EMV)

»
i.e. putting a financial value to the expected
result of a risk.

»
Allows a quantification of a risk outcome


Expected Net Present Value (ENPV)

»
Also used for appraising the financial nature
of long term projects

»
an extension of EMV by calculating the
present value of a probability state


Decision Analysis

»
looks at possible outcomes and determining
optimal choices

more...

Risk Estimation
cont

Quantitative Techniques
cont


Sensitivity Analysis

»
tests how sensitive an event outcome is to
slight changes on the input variables.


Delphi peer groups

»
a Delphi group will pool the knowledge &
experience of a number of experts

»
attempts to put quantitative values to results
obtained in a manner similar to discussion
groups and brainstorming.


Simulation

»
creates a probable life history of an event and
thus allows its outcome to be predicted.

BS8444
-
3: 1996


Estimation methods

BS8444
-
3: 1996


Additional estimation
methods

Risk Evaluation


3rd part of
Risk Assessment


Need to combine the severity and
probability of the identified hazards


Allows
tolerability decisions
to be made


Can be done using a risk matrix:

Category of
Occurence
Frequency
of
Occurence
Consequences
/ year
Catastrophic
Major
Severe
Minor
Frequent
>1
H
H
H
I
Probable
1 to 10
-1
H
H
I
L
Occasional
10
-1
to 10
-2
H
H
L
L
Remote
10
-2
to 10
-4
H
H
L
L
Improbable
10
-4
to 10
-6
H
I
L
T
Incredible
< 10
-6
I
I
T
T
Risk Evaluation


BS8444
-
3: 1996

Practical Risk Assessment Procedure

1.
Identify the principal hazards that will be
present in the operation.

2.
Assign a number 1 to 5 for both
Consequences of Hazard
and

Probability of
Occurrence.


The
Risk

(i.e. the product of
Consequence and
Probability
), indicates the level of action.

3.
Identify persons affected by the risk

4.
Respond to the risk

5.
Monitor and update as necessary.


Risk Response


If risks are identified as being
intolerable

how can these be dealt with?


There are four main methods of
responding to such risks:

1.
Risk Avoidance

2.
Risk Transfer

3.
Risk Retention

4.
Risk Reduction


British standards and other textbooks
offer the least guidance on this stage


Because responses
must

be designed to
fit the situation

Risk Response

1. Risk Avoidance


Managing

or developing a situation in
which the identified risks do not occur,
e.g:


not proceeding with the project


tendering at a very high bid


placing conditions on a bid


changing design


choosing different currency


... ?

Risk Response cont

2. Risk Transfer


Via Subcontractors


a third party undertakes the high risk portion
of the work and the responsibility that goes
with it


Via Insurance


A pre
-
determined insurance premium is often
better than unexpected costs due to risk


may be done using a
captive

insurance
company


involves excesses


some risks may result in premiums higher
than the probable financial loss

Risk Response cont

3. Risk Retention


Some risks may be better managed internally


High frequency/low severity or very low
frequency/high severity risks may be best
retained

4. Risk Reduction


The most usual way in which to manage
common risks is to reduce either the severity,
the chance of occurrence or both. E.g:


early warning systems

»
R
educes
probability

of hazard happening


improved maintenance

»
Reduces
probability

of failure


physical mitigations

»
May reduce both
probability
or
severity

Risk Response cont


The choice of method used to respond to
risk will largely depend on company policy


Using the risk matrix model, a typical
project scenario
may

be:

Category of
Occurence
Consequences
Catastrophic
Major
Severe
Minor
Frequent
Transfer
Transfer
Retain
Avoid
Probable
Reduce
Transfer
Retain
Avoid
Occasional
Reduce
Transfer
Transfer
Retain
Remote
Reduce
Transfer
Transfer
Retain
Improbable
Avoid
Transfer
Transfer
Retain
Incredible
Avoid
Transfer
Transfer
Retain
Risk Monitoring


The final stage of risk management


Risk situation will continue to change
throughout the life of the project


New hazards will become present


Existing hazards will stop or change


The management must be continually
monitored, reviewed and improved


Existing risks may be managed
differently

»
therefore


Risk monitoring completes cycle back to
risk identification

Risk Monitoring


Risk situation
will continue
to change
throughout
the life of the
project


New
hazards will
become
present


Existing
hazards will
stop or
change

Remove
mitigations

NO

Does
existing
hazard
still
exist?

Has the
probability
of
occurrence
increased?

(Re)Assess
Risk

Has the
severity of
potential
harm
increased?

Have new
hazards
arisen?

Do nothing

Do nothing

YES

YES

YES

NO

NO