Hazop Study Guidelines
B&R-C
Code du document : DOP1000-WMT-001-0-04
Date : 23 Mars 2004
Indice de revision : 0
Page : 1 / 9
Mots cls: Hazop, Guidelines
HAZOP STUDY GUIDELINES
Evolution du document:
Date
23.03.04
Indice
0
Objet de la modification
Cration
Rdige par: S.Benkhaled
Vrifie par: N.Iguertsira
Approuve par: T.Ferhat
NB/ La procdure signe est disponible au niveau de la Direction Qualit.
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
Code du document : DOP1000-WMT-001-0-04
B&R-C
Date : 23 Mars 2004
Indice de revision : 0
Page : 2 / 9
TABLE OF CONTENT
Cover Page ......1
Content Page ... .....2
1.0 INTRODUCTION .3
1.1 Purpose .3
1.2 Objectives .3
1.3 IMPLEMENTATION 3
2.0 HAZOP BASIS 3
2.1
2.2
2.3
2.4
2.5
2.6
Information 3
Method ..4
Review team .5
Timing 5
Results ...5
HAZOP Procedures 6
3.0 APPENDICES .7
A-1 Information List for HAZOP Study ..7
A-2 HAZOP Deviation Matrix ..8
A-3 Example of HAZOP Worksheet ..9
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
Code du document : DOP1000-WMT-001-0-04
B&R-C
1.0
Date : 23 Mars 2004
Indice de revision : 0
Page : 3 / 9
INTRODUCTION
1.1
Purpose
Purpose of this work method is to provide safe and operability hydrocarbon facilities. On a
project, losses to life, environment, and investment due to process hazard could be catastrophic. It
is therefore prudent to develop and manage a process hazard analysis.
1.2
Objective
The main objective of this program is to prevent the occurrence, or minimize the consequences of
catastrophic releases of hydrocarbon materials. This will be accomplished by systematically
addressing the following:
Evaluation of the safety of the hydrocarbon facilities.
Evaluation of the operability of the hydrocarbon facilities.
Review of the operating outlines.
Determination of the correctives actions.
Prioritization of the corrective actions.
Assurances that correctives actions are implemented.
Regardless of the hazard analysis technique, the process hazard analysis will focus on safety
hazards and operability problems that could lead to the following:
Endanger safety of operating personnel.
Endanger safety of neighboring general public.
Result in a loss of production.
Cause extensive equipment damage.
Product large quantities of off-spec product.
Result in environmental impacts.
The physical limit or boundary of the process hazard analysis will normally be the inside battery
limits of the gas dehydration unit.
1.3
Implementation
The process hazard analysis program is to be implemented in the fo llowing manner. A third party
will be charged for the facilitation of the HAZOP. The advantage is that a third party facilitator
will have an unbiased point-ofview. The HAZOP is most effectively performed once the P&IDs
are firm. A management of change design-freeze should already be in-place in the sense that
any changes to the P&IDs are logged and eventually reviewed from a HAZOP perspective.
2.0
Hazard and Operability Study Basis
2.1
Information
The hazard and operability analysis will be conducted during detailed engineering. The primary
document used is the P&IDs issued for design. In addition to P&IDs, the process flow diagram,
start-up and shutdown logic diagrams, equipment and instrument datasheets, detailed plot plan,
safeguarding memorandum and operating procedures are needed. A list of information needed for
the HAZOP is identified on appendix A-1.
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
B&R-C
2.2
Code du document : DOP1000-WMT-001-0-04
Date : 23 Mars 2004
Indice de revision : 0
Page : 4 / 9
Method
The HAZOP technique is a means of systematically reviewing a process to identify potentially
hazardous events that could occur, or operability problems in the design. It is a team technique. A
HAZOP study is conducted by a team led by a facilitator knowledgeable and experienced with the
HAZOP technique. A set of guide-words is used by the team to help ensure the thoroughness and
structured approach of the study. The guide-words are combined with process parameters to
develop deviations. The HAZOP Deviation Matrix in appendix A -2 illustrates the application of
this concept.
The technique is based on the premise that a hazard may occur if the process deviates from the
design intent. The team determines if the deviation could realistically occur, and if so, makes an
assessment on whether the consequences constitute a hazard or operability problem. The team then
evaluates whether existing safeguards, both as hardware or procedure, are adequate considering the
causes and consequences of the deviation. If necessary, the team makes a recommendation for
improvement or for a study to determine an optimal solution or for additional investigation
whether a problem exists that warrants any action.
At each HAZOP session (team meeting), the discussions of the team are recorded on a HAZOP
worksheet. A work sheet example is provided in appendix A-3. This documentation will show
which study nodes (segments of process) were reviewed, which guide-words and parameters were
considered, the causes and consequences of a deviation, whether the existing safeguard in the
design are considered adequate, and if not, what action is recommended.
The basic purpose of the HAZOP is to identify potentially hazardous scenarios or operability
problems. Therefore, the team should not spend any significant time trying to engineer a solution if
a potential problem is uncovered. If a solution to the problem is obvious, the team should
recommend a correction immediately. If a solution is not obvious, the team should recommend that
someone follow up and resolve the problem outside the HAZOP study. Also, if there is insufficient
information available at the time to decide if a potential problem exists, the team should note it,
assign someone to collect the additional information, and continue with the study.
Key terms that are used in HAZOP technique or worksheet are briefly defined as follows:
NODE
The discrete location on the P&IDs at which the process parameters
are investigated for deviation. A node can be a piece of equipment, a
section of piping, or several interconnected sections piping and
equipment that perform a specific function.
INTENTION
Expected operating state for the node.
PARAMETER
Physical or chemical property associated with the process (temperature,
pressure, etc).
GUIDE-WORDS
Simple words which are used to qualify or quantify the intention and to
guide and simulate the brainstorming process for identifying process
hazards.
DEVIATION
Departure from the design intention.
CAUSES
Reasons why deviation might occur.
CONSEQUENCES
Effects of deviations.
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
Code du document : DOP1000-WMT-001-0-04
B&R-C
Date : 23 Mars 2004
SAFEGUARDS
2.3
Indice de revision : 0
Page : 5 / 9
Features designed to prevent the causes or mitigate the consequences of
the deviations.
Review Team
The composition of the review team will usually consist of the following members:
Client representatives ( if necessary )
B&R-Cs project engineer
B&R-C process engineer
B&R-C instrument engineer
Third party facilitator and scribe
In addition to the above team, certain B&R-C specialists should be on-call to provide any
expertise the regular team members may lack.
Desirable characteristics of the members are:
2.4
Knowledge of engineering, safety and loss prevention standards and codes
Operations and maintenance experience
Understanding of the method of HAZOP (especially facilitator)
Intellectual curiosity
Imagination
Timing
The scheduling of the HAZOP should be as soon as possible after the issuance of the P&IDs for
design. This will ensure the design is firm enough to allow meaningful answers to the questions
raised during the HAZOP team meetings. HAZOP team meeting should be limited to 6hours per
day and five days per week.
2.5
Results
The HAZOP meetings will result in recommendation to remedy potential safety or operability
problems and/or the need for additional information or analysis. As the duration of the HAZOP
study is significant, it is advisable that recommendation that could result in design changes are
evaluated and if necessary incorporated prior to completion of the HAZOP study.
The draft HAZOP report will be prepared by the third party facilitator and delivered to the project
management within four weeks of the team meeting. The final design report, with comments
incorporated, will be released by the facilitator to the management for distribution. The report
should not be held up for follow-up analysis or studies. The action plan to carry out the HAZOP
study results and follow-up analysis is performed outside of the HAZOP study report. Resolved
action items and follow-up analysis are normally distributed by the project management as a standalone addendum to the HAZOP study report.
The HAZOP report will contain the following:
1. Introduction
Process description
Scope of the study
Study Objectives
Team membership and qualifications
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
B&R-C
Code du document : DOP1000-WMT-001-0-04
Date : 23 Mars 2004
Indice de revision : 0
Page : 6 / 9
Listing of near misses and previous incidences
2. Methodology Hazard identification
Hazard analysis
3. Study Results
4. Appendix
2.6
HAZOP study worksheets
HAZOP Procedure
The facilitator will give an introductory HAZOP training session to the participants on the first
meeting day. An active HAZOP worksheet is projected for interaction with the team as hazard
scenarios or operating problems are discussed so the team can see the recorded results on a real
time basis. The facilitator has to encourage active participation by the team. The HAZOP facilitator
and the project engineer will control the degree of problem solving that occurs during the meeting
and keep the focus on the information being reviewed.
The facilitator will generate a hard copy of the HAZOP worksheets at the conclusion of each day
for the participants. At the beginning of the following session day, any comments from participants
on the previous session worksheets will be reviewed and if accepted by the team, incorporated. At
the conclusion of the HAZOP study, the entire list of recommended action items will be reviewed.
The facilitator will prepare a draft of the report. Copies of the draft report will be distributed to
HAZOP review team. The project engineers consolidate these comments. The goal is to complete
the draft report in three weeks. After incorporating and/or resolutions of the comments, the
facilitator will sent the required number of copies of the final design HAZOP report to the project
engineer for project distribution.
The project engineer will ensure that an accurate log of all design changes is in place at the time
information is gathered for the HAZOP study. Ideally a design freeze will be in effect on the
P&IDs prior to this and design changes should be less prevalent. However, some changes are
inevitable and these must be thoroughly reviewed for safety. An assessment of the impact of these
changes on the HAZOP study results is required.
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
B&R-C
3.0
Code du document : DOP1000-WMT-001-0-04
Date : 23 Mars 2004
Indice de revision : 0
Page : 7 / 9
Appendices
Appendix A-1: INFORMATION LIST FOR HAZOP STUDY
Copies for
HAZOP meeting
1.
Process Flow Diagram (PFD)
..
2.
P&IDs
..
3.
Plot Plan
..
4.
Equipment Specifications Datasheets
..
5.
Safeguarding memorandum
..
6.
Start-up and shutdown logic diagram
..
7.
Operating procedures for start-up, normal operation
And emergency shutdown
..
8.
Material Safety Datasheets for hazardous substances
..
9.
An incident list that have occurred in this type of plant
..
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
B&R-C
Code du document : DOP1000-WMT-001-0-04
Date : 23 Mars 2004
Indice de revision : 0
Page : 8 / 9
Appendix A-2: HAZOP DEVIATION MATRIX
Process parameters
Special
Guide-Words
Flow
Pressure
Temperature
No, Not, None
No flow
Open to Freezing
Atmosphere
Less, Low, Short
Low Flow
Low Pressure
Part of
Wrong
Concentration
More, High
Level
Empty
Utility
Failure
Low Temp.
Low Level
Leak
N/A
N/A
Low interface
Tube
leak
High Flow
High Pressure
High Temp.
High Level
Rupture
As well as,
Also
Contaminates
misdirection
N/A
N/A
High interface
Tube
repair
Reverse
Backflow
Vacuum
N/A
N/A
Other than
Wrong
Material
N/A
N/A
N/A
Auto-refrigeration
N/A
Appendix A-3: Example of HAZOP Worksheet
Company
Facility
Session date
Node
P&ID
Parameters
Intention
:
:
:
:
:
:
:
SONATRACH
Gas dehydration Unit
Scrubber 200-V-04
UDA-200-DG-PR-008-1/3
Flow, Pressure, Temperature
Separate wet gas, condensate and water
Le prsent document est la proprit exclusive de B&R-C.
Hazop Study Guidelines
Code du document : DOP1000-WMT-001-0-04
B&R-C
Deviation
Date : 23 Mars 2004
Causes
Consequences
Indice de revision : 0
Page : 9 / 9
Safeguards
Recommendations
Le prsent document est la proprit exclusive de B&R-C.
