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 risks to personnel or equipment, or prevent efficient operation. A HAZOP is a qualitative technique based on guide-words and is carried out by a HAZOP team during a set of meetings

1. Presented By:
Ashwani Kumar (2012-65)
Sagar Verma(2012-07)

2. What is HAZOP?
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 risks to
personnel or equipment, or prevent efficient
operation. A HAZOP is a qualitative technique based
on guide-words and is carried out by a HAZOP team
during a set of meetings.
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3. BACK GROUND
 The HAZOP technique was initially developed to analyze chemical
process systems, but has later been extended to other types of systems.
 First main textbook: Kletz, T. A.: “Hazop and Hazan -Identifying
and Assessing Process Industry Hazards”, Institution of Chemical
Engineers.
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4. When to Use?
Optimal from a cost viewpoint
1. when applied to new plants at the point where the
design is nearly firm and documented or
2.to existing plants where a major redesign is planned.
It can also be used for existing facilities.

5. Principles of HAZOP
Concept
•Systems work well when operating under design conditions.
•Problems arise when deviations from design conditions occur.
Basis
•a word model, a process flow sheet (PFD) or a piping and
instrumentation diagram (P&ID)
Method
•use guide words to question every part of process to discover what
deviations from the intention of design can occur and what are their causes
and consequences may be.

6. GUIDE WORDS
Guide Words
No, None
More Of
Less Of
As Well As (More Than)
Part Of
Reverse
Other Than
Meaning
Negation of Intention
Quantitative Increase
Quantitative Decrease
Qualitative Increase
Qualitative Decrease
Logical Opposite of
Intention
Complete Substitution

7. EXAMPLE
The flowsheet shows that raw material streams A and B are transferred by
pump to a reactor, where they react to form product C. Assume that the
flow rate of B should not exceed that of A. Otherwise, an explosion may
occur. Let’s consider the flow of A in line 1:
NONE No flow of A
MORE Flow of A greater than design flow
LESS Flow of A less than design flow
AS WELL AS Transfer of some component additional to A
PART OF Failure to transfer a component of A
REVERSE Flow of A in a direction opposite to design direction
OTHER THAN Transfer of some material other than A
A B
C
B
A
B F
F 

8. Types of HAZOP
 Process HAZOP:
 Human HAZOP :
 Procedure HAZOP:
 Software HAZOP:
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9. Process HAZOP
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10. Human Hazop

11. Procedure Hazop

12. Software Hazop

13. Have a Nice day.!!!!!