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.
BY: IHSAN ALI WASSAN
Quaid-e-Awam University of Engineering Science & Technology, Nawabshah, Sindh Pakistan
Where HAZOP is used ?
Seven Steps of HAZOP study?
You and your family are on a road trip by using a car in the middle of
the night. You were replying a text message while driving at 100
km/h and it was raining heavily. The car hits a deep hole and one of
your tire blows. You hit the brake, but due to slippery road and your
car tire thread was thin, the car skidded and was thrown off the
POINTS TO PONDER
What is the cause of the accident?
What is the consequence of the event?
What can we do to prevent all those things to happen in the first place?
What other possible accidents might happen on the road trip?
Can we be prepared before the accident occurs?
Can we make it more systematic?
Parameter Guideword Possible
Consequences Action Safeguard
Car speed Too fast
Rushing Skidded when
- Slow down
- Speed up
-ABS brake system
- Air bag
Tire No thread
Tire too old, often
Car skidded - Check frequently
- Have spare tire
Rain Cannot see the road
Car light Dim
-Go to nearest garage
-Use emergency signal
Road With holes
Breaks the car tire - Put a signboard
Travel time Night
No street light -Travel during daylight
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.
A HAZOP is a process to identify and Access risks.
The HAZOP technique was initially developed to analyze chemical process systems,
but has later been extended to other types of system.
• HAZOP technique is used by most major companies handling and
processing hazardous material,
- oil and gas production
- flammable and toxic chemicals
- pharmaceuticals etc
Where HAZOP is used ?
7 steps of HAZOP ?
Let’s break down a HAZOP into 7 steps:
1. Identify the Risk by asking what can cause a hazardous event.
2. Describe the consequence and assign a severity level.
3. Assess the probability of the cause.
4. Evaluate the Risk based on the severity and probability without any safeguards
5. Look up your Risk Matrix to categorize the Risk.
6. Assess the Risk with Safeguards
7. Make a decision to accept the Risk or make a recommendation to further reduce