A HAZOP (Hazard and Operability) study is a systematic technique used to identify potential hazards and operability problems in processes. It involves a team reviewing a process and its design to identify possible deviations from safe operation. The document outlines the HAZOP process including preparation, terminology, meeting procedures, follow up actions and documentation. Key aspects include selecting a team with relevant expertise, gathering process information, using guide words to identify deviations, assessing risks, recommending safeguards, and documenting actions.

1. A Report on HAZOP Analysis

2. CONTENTS
1. Introduction
2. HAZOP Preparation
 Selection of HAZOP study team members
 Information required for HAZOP study
 Other responsibilities
3. HAZOP Terminology
 System
 Design Intent
 HAZOP Guide words
 Safeguards & Recommendations
 HAZOP Study Record & Risk Assessment
4. HAZOP Meeting Procedure
5. HAZOP Following Up actions
6. HAZOP Closure
7. Documentation

3. 1. Introduction
Increasing demand by governments and public bodies for improved safety in addition
to a strong awareness within the industry that safe operation can also be highly efficient
and profitable, support the need for plant safety and effective safety management.
Advances in technology and trends to highly complex and integrated plant designs have
sensitized people for systematic and sustainable methods to identify hazards of which the
HAZOP study is generally recognized as the foremost solution being able to cover standard
and also new complex technology.
A Hazard and Operability (HAZOP) study is a structured and systematic examination of
a planned or existing process or operation in order to identify and evaluate problems that
may represent a risk to personnel or equipment, or prevent efficient operation. A HAZOP is
a qualitative technique based on "guide words" and is carried out by a multi-disciplinary
team (the HAZOP Team) during one or more meetings.
A HAZOP is a design verification process. It should not be used as a design development
process. The HAZOP should be performed at the stage in the design process when all
preliminary engineering is complete and the basic design has been fixed. This includes
complete process design, process flow diagrams, P&ID’s, plant and equipment layout,
operating philosophy, control and instrumentation philosophy, utilities requirements,
specification and selection of major equipment items, protection systems, start up and
shutdown systems.
2. HAZOP Preparation
It is the responsibility of the Responsible Officer to initiate the HAZOP study where the
project or modification meets the criteria.
 Selection of HAZOP study team members:
The Responsible Officer will first appoint an independent HAZOP Leader to act as
the Chairperson for the HAZOP meetings. The HAZOP Leader must be trained in HAZOP
methodology and have successfully completed a suitably recognised HAZOP Leader
Course, or equivalent experience, as approved by the Manager - Project Engineering.
The HAZOP Leader should be independent, i.e. with no responsibility for the process or
operations in the area where the process being reviewed is located.

4. HAZOP studies will be conducted using a team approach, with a minimum of four
members. The Responsible Officer together with the HAZOP Leader will select the
HAZOP team members to achieve the spread of knowledge and skills required for the
particular project, and may include:
1. Representative of the customer
2. A person with Process knowledge
3. A person with Safety & Environmental knowledge
4. A person with operating and/or maintenance experience in comparable
environment.
5. A person with Engineering/Design knowledge

5.  Information required for HAZOP study
The following information should be assembled by the Responsible Officer and the
HAZOP Leader before the HAZOP study team commences work.
Essential Items:
1. Functionally complete P & ID for the process
2. System design philosophy and process description
Desirable Items:
1. Plot plans or layouts
2. Process flow diagrams
3. Piping class specifications
4. Equipment data sheets and purchase specifications
5. Vessel inventories
6. Relief valve specifications
7. Start up and emergency shut-down procedures
8. Emergency depressurizing system functions
9. Electrical area classification
10. Standards used
11. Procedures - operating and maintenance as applicable
 Other responsibilities
The Responsible Officer is responsible for the following HAZOP study arrangements:
1. Organizing meeting dates, venue and notices to the attendees
2. Layout of venue and supply of stationery and other resources for the meeting
3. Provision of information required for the HAZOP study
4. Close out meeting date, venue and notice to the attendees.

6. 3. HAZOP Terminology
 SYSTEM
A System is a specific location or logical part of the process or operation in which
possible deviations from the design intent are to be evaluated. Examples might be a heat

7. exchanger, vessel, pump, compressor and interconnecting pipeline or group of lines.
Systems should be progressively identified on the P&ID as the HAZOP study proceeds.
 DESIGN INTENT
The design intent is a description of how the process is expected to behave at the
system being studied. This is qualitatively described as an activity eg feed, reaction,
transfer, heating, and quantitatively in process parameters such as pressure, temperature,
flow rate.
 HAZOP GUIDE WORDS
All possible deviations in process parameters in a reactor or a pipeline are
considered to determine their causes and consequences. If a hazard is identified, first the
existing protective measures are analyzed with respect to the intensity of the hazard. If the
protective measures are not adequate, recommendations are given to mitigate the hazard.
HAZOP study involves a set of standardized GUIDEWORDS, which are required to initiate

8. analysis.
Examples of process parameters include the following:
Each guide word is combined with relevant process parameters and applied at each point
(study node, process section, or operating step) in the process that is being examined.

9. The following Table showed examples of creating deviation using guide words and
process parameters:
 Safeguards
Safeguards are facilities, processes or procedures that help to reduce the likelihood
or frequency of the deviation, or to mitigate its consequences.
Examples of safeguards include the following.
1. Procedures to define what actions to take in the event of a deviation.
2. Increased frequency of inspection, servicing or calibration of critical items.
3. Facilities that draw attention to the deviation (eg indicators and alarms to inform
operators so that they can make the process safe).
4. Facilities that automatically compensate for the deviation (eg an automatic control.
5. System, usually an integrated part of the process control).
6. Facilities that prevent the deviation from occurring (eg excess flow valve).
7. Facilities that prevent further escalation of the deviation (eg by total trip of the
activity or process by a safety interlock, control system, or emergency shutdown
(ESD) system).
8. Facilities that relieve the process from a hazardous deviation (eg pressure safety
valve (PSV) and vent systems)
As each cause and consequence scenario is identified, planned safeguards should be
reviewed to determine if they are adequate to either prevent the deviation or to protect the
System if the deviation occurs. Any decision on the adequacy of the safeguards should take
into consideration the magnitude of the potential consequences and the likelihood of the
event occurring with all the planned safeguards in place. This is reflected in the risk
assessment as below. Each scenario will usually have more than a single layer of protection.
For high risk deviations, it is useful to review each of the layers of protection before
determining the adequacy of the safeguards.

10.  Recommendations
If the HAZOP Team recommends that additional safeguards or changes to the design
should be made to ensure the safety of the system, these recommendations must be
recorded on the HAZOP Record for further action after the HAZOP study. The name of the
person who will be responsible for the further actions should be recorded on the form next
to the assigned action.
 HAZOP study record
HAZOP Study Record form is used to create a historic record of the HAZOP Study.
Details of discussions, decisions taken, risk assessments made and further actions
recommended during evaluation of each of the HAZOP Study Cards will be progressively
recorded by the HAZOP Secretary on the HAZOP Study Record form.
 Risk Assessment
Risk assessments should be carried out to quantify the risks associated with
deviations and their potential consequences, and to assist in determining the adequacy of
planned safeguards and the possible need for further action. An initial informal risk
assessment should be carried out on each cause - consequence scenario based on the
inherent risk in the unprotected state.
The Risk Matrix included in the below table should be used as a guide. The risk
should then be re-assessed taking into consideration the planned safeguards and risk
reduction measures. For less important risks, the need for further action can be based on
the experience and judgment of the HAZOP Study Team.

11. Once the reasonable consequence and likelihood of each potential unwanted event
is determined, the risk can be ranked using the “Risk Assessment Matrix” below and
recorded on the HAZOP Study Record sheet.
For high risk scenarios, several layers of protection will usually be necessary to
reduce the risk to an acceptable level. If the HAZOP team agrees that, so long as the planned

12. safeguards are in place, the risk of an unwanted event occurring is reduced to an acceptable
level, then no further action is required.
For extreme risk scenarios, the adequacy of safeguards and the need for further
action should be quantitatively assessed using higher level risk assessment techniques
such as Layer of Protection Analysis (LOPA), or Safety Integrity Level (SIL) analysis. The
risk assessment process and outcome should be recorded on the HAZOP Study Record form
against each item.
4. HAZOP Meeting Procedure
At the HAZOP meeting, the HAZOP Leader will act as Chairperson to lead the team
through each of the following steps.
a) Introduce the project:
 Ensure all team members are familiar with the HAZOP process
 Define the project for the team
 Review the proposed process or modification using the Process and
Instrumentation Diagram (P&ID) and describe its operation
 On the P&ID, divide the process to be studied into logical Systems.
b) Carry out HAZOP Study:
 Select a particular System for detailed review and describe the design intent for that
System. Work through the guide words on the HAZOP Study Cards, following the
HAZOP Process Flow Chart.
 For each guide word, establish if the deviation from normal conditions suggested by
the guide word could occur. If the deviation could occur, identify the possible causes
of the deviation.
 Determine the possible consequences or problems if the deviation occurred.
 Carry out an initial assessment of the risk associated with the identified
consequences Review any proposed safeguards to prevent or mitigate the
consequences.
 Evaluate if the proposed safeguards adequately reduce the risk to an acceptable
level and if not, suggest further actions having regard to the consequences and the
safeguards already proposed.
 Repeat procedure from [step (a)] above for the next System. Progressively complete
HAZOP Study Record form including recording of further actions.

13. Modifications must be assessed for impact during a variety of plant conditions (ie.
startup, running, plant upset, and plant shutdown). This aspect will be formally
documented where appropriate throughout the HAZOP, and must also feature as a specific
element considered within the agreement and sign-off of the final records of the HAZOP.
5. HAZOP Following Up actions
The Responsible Officer shall ensure that all actions arising from the HAZOP are
properly managed and are completed prior to commencing the modification or
HAZOP PROCESS FLOW CHART

14. commissioning the modified plant as determined during the HAZOP. The items recorded on
the HAZOP Study Record form SF1309 as requiring action shall be numbered and a
required date of completion established. This information shall be entered into the
“Recommendations” column on the HAZOP Study Record.
6. HAZOP Closure
When all follow-up actions are complete, the Responsible Officer shall note on the
HAZOP Study Record of Discussions (SF 1909) that all items have been completed and
make reference to the Inspection Reference Number in Cintellate. To assist in later
verification, a copy of the complete Cintellate record should be printed out after all actions
have been completed and attached to the HAZOP Study Record in the Project file.
Close out meeting:
The Responsible Officer will arrange a close out meeting to record completion of
outstanding issues.
Once all parties are satisfied that all issues arising from the study have been
adequately addressed and are reflected in the project design documentation, form HAZOP
Study Record of Discussions form shall be completed and signed off by the Responsible
Officer and the Customer Representative.
No commissioning activities associated with the modification or the new plant
covered by the HAZOP shall commence until form HAZOP Study Record of Discussions
(SF1909) has been signed off.
7. Documentation
The following HAZOP study information and documents are required for the files:
a) HAZOP Study Record which includes:
 Project title
 Project number (that is, work order number for the parent project)
 Project scope
 Study date
 Participant names, job titles, organisation, brief profile
b) Signed off HAZOP Study Record of Discussions
c) The original copy of all P&IDs used in the study (with lines clearly identified)
d) Variations in guide words used.

15. e) Signed off Action Summary sheet
f) Signed off HAZOP Action sheets
The study Responsible Officer is responsible for the preparation and collation of the
output documentation from the HAZOP study, and for forwarding it to all attendees,
including the Chairperson who should sign off the HAZOP Study Record before filing by the
Responsible Officer.
The Responsible Officer ensures an electronic copy the documentation listed above
is filed in the Domino. Doc System in accordance with Management of Risk Assessment
Records. A hard copy of all this documentation will also be filed in the Project File by the
Project Officer.