>> Site Map >> Forums >> Support
Forum module - topics in forum:
Support - Need any safety assistance... post your request here.
HAZOP
I am having great difficulty locating information to draw up a hazop for an assignment. I can find lots of stuff but I can't find an example of a completed, simple diagram. can anyone help with either where I can look or an A4 size diagram of an example?
A HAZOP is structured technique identifying hazards resulting from potential malfunctions in the process. It is a qualitative process undertaken by a multi-disciplinary team asking a series of "what if?" questions. By undertaking a HAZOP study at an early design stage, potential problems can be avoided at the design stage. The team systematically examine a proposed process design by asking questions using guidewords representing deviations from the intended parameters of the process.
A worked example is the delivery of liquid propane to a fixed tank fitted with a pressure relief valve and a liquid level gauge:
Deviation
Cause of deviation
Consequences
Existing controls
Possible action
More level
Overfilling - Human error
Pump fails ON
Release through relief valve
As above
Level gauge
As above
Consider high level alarm
As above
Less level
Leak
Not filled properly - Human error
Release to atmosphere
Economic losses
None
Level gauge
Review inspection/maintenance regime and consider gas detectors
More temperature
Fire near vessel
Possible release and escalation
None
Consider automatic sprinkler and fire procedures
More pressure
Relief valve fails closed
Vessel overpressure/rupture
None
Consider high pressure alarm
Less pressure
Relief valve fails open
Filling hose ruptures
Release to atmosphere
As above
None
Operator action
Consider detection and emergency planning
Check integrity of hose and quality control
As well as
Water contamination
Impurities
Out of spec. supply
As above
None
None
Review QA procedures
As above and can reaction occur
Other than
Wrong substance delivered
Possible reaction
None
Review QA procedures/can reaction occur
Hope this helps
Mike
