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Transcript of Moc
Management of Change
An Essential Process Safety Management Element.
Outline
• What is Management of Change (MOC)
• Why do we need MOC
• Recognizing Change
• The MOC Program– Main Elements – Operation– Keys to Success
Management of Change
• “Policies and procedures which ensure that changes do not result in operations outside of established safety parameters”
• Essential element in a plant’s process safety system
• Managing change can mean managing potential incidents
Focus of MOC
• To prevent catastrophic accidents and to properly evaluate the concerns of safety and health and to accomplish this review in a timely manner.
History of MOC• Early 60s - Formal procedures first introduced in
the nuclear power and defense industries.• 1976 - First mention of use within chemical
industry at Loss Prevention Symposium• 1985 - CCPA pamphlet, “Essential Components of
Safety Assessment Systems• 1990 - API recommended practice “Management
of Process Hazards”• 1992 - OSHA 1910.119, “Process Safety
Management of Highly Hazardous Chemicals”
MOC and PSM• PSM is a method of identifying,
understanding, and controlling process hazards and preventing process-related injuries and accidents
• MOC is one of the 12 PSM elements• MOC is different from the other elements
– MOC is never complete - must be performed on a continual basis throughout the life of the plant.
Why do we need MOC?
• 80% of all large scale accidents in the process industries trace their origins back to “Change”.
• Change is essential to a company’s survival– they have to be able
to continuously improve their process and keep up with industry standards.
VS.
Case Study: Flixborough
• Vapor cloud explosion - fueled by release of 30 tons of cyclohexane
• Largest single loss by fire or explosion in the United Kingdom– killed 28 people– injured 89 others– $63 million in property damage
Cause: Temporary Modification
12
34
56
Bellows
Why did the Bypass Piping Fail
• No safety review and inadequate supervision
• Job was beyond professional capabilities of the workers
• Only drawing was a full-size sketch in chalk on the workshop floor.
• No one understood the forces that would be imposed on the pressurized piping
In Hindsight ...
• A proper MOC procedure could have prevented this accident.
• One of Main recommendations from inquiry– Any modification should be designed,
constructed, tested, and maintained to the same standards as the original plant.
Do any of you ever need to Manage
Change???
Everyday Life Examples
• Computer software– when you
upgrade/add one component - will it be compatible with the rest of your system?
Everyday Life Examples
• Adding a course to your schedule– does it conflict with your other courses?– does it meet your graduation requirements?
• Driving on the highway when it is icy– does the speed limit still apply or should you
reduce your speed?
What is Change?
• Most difficult part of Management of Change is recognizing change.
• Need to be able to distinguish between a change that requires approval using the MOC procedure and one that does not.
Recognizing Change
1000 Work Orders
50-100 MOC
5-10 potentially high risk
Replacements-in-kind
• Def. - a replacement that satisfies the design specifications.
• Examples– raising reactor temp. within safe operating
envelope– replacing equipment or piping meeting the
same specifications as the original
Change
• Change is an alteration or adjustment to any component, variable or property within an existing system (except those within clearly defined boundaries or responsibilities).
• Examples– changes that alter production rates– changes involving safety relief or vent systems– deteriorating materials
Change or Replacement-in-kind?
• Changing metallurgy of a piping system.
• Recalibrating instruments
• Operating with a heat exchanger out of service
• Replacement of gate valves with ball valves (within the plant valve specifications)
Case Study - Beware of Hidden Changes!
• Vapor cloud explosion and major fire within a refinery– 7 deaths– 13 injuries– $35 million in losses (half in property damage,
half in business interruption)
• Cause: Hidden Change to a valve !!!
Case Study - Beware of Hidden Changes
• Storage tank containing flashing, flammable fluid.
• Tank connected to process unit via 10” line
• Corrosion attacked valve bonnet bolts and weakened them.
• Bonnet was blown off and an uncontrolled, catastrophic release occurred.
Main Types of Changes
• Change of Process Technology
• Change of Facility
• Organization Change
• Variance Procedures
Permanent vs. Temporary
• MOC should be conducted on both permanent and temporary changes.
Emergency Changes• Sometimes you have no choice and you have
to make a change without going through the proper approval process.
• Need a contingency plan
• Evaluate using limited skills and resources - focusing on immediate risk only.
• When normal operations resume - implement a full MOC evaluation.
Key Elements of a Program
• Identification System
• Change Control Mechanism
• Training
• Information Management System
• Auditing
Note - The requirements for each element are detailed in a company’s MOC policy
Identification System
• Screening process for identifying changes.– Includes risk ranking process based
on effect item could have on safety of process
• Requires clear, written, definition of system boundaries and what constitutes “change”
Change Control Mechanism
• Explains how to manage the change.
• Must clearly identify:– the work flow procedures (MOC form)– responsibility and authority– approval level
Training
• Anyone who could affect a change must be properly trained in the Management of Change system
• Commitment from all levels of management and staff
Information Management System
• “Status Accounting”
• Software/documentation that tracks all changes and their progress
• Allows access to most current information– eg. If two changes are inter-related
they will be aware of one another
Auditing
• Ensures system is working as it should
• MOC system should be constantly evolving and improving in efficiency and effectiveness
• Verifies changes are assessed accurately
• More often while the system is new to ensure all the “bugs” are found
Operating the MOC system
• A MOC system is very dependent on the specific company– no two systems will be the same– eg. one company could require 1 signature for
approval while another could require 5.
• They are all based on the same fundamental principles
IDENTIFY CHANGE
DETERMINE SIGNIFICANCE OF
CHANGE
SIMPLE RISK ASSESSMENT
REVIEW WITH TEAM LEADER
FOLLOW-UP
APPROPRIATE RISK ASSESSMENT
APPROVAL
TRAINING AND COMMUNICATION
IMPLEMENT CHANGE
LOW
LOW RISK
UNCERTAINMEDIUM/ HIGHFlowchart of a
Management of Change Program
MOC Form
• A MOC form is used by most companies to guide employees through the procedure
• The MOC form should include:– Description, purpose, and tech. basis for the change
– Assigned level of risk
– Safety, Environmental, and Health impacts
– Necessary time period for the change
– Authorization for the proposed change
– Interfaces with the PSSR program
Ranking changes
• Must delineate changes– small– medium– large
• Don’t manage all changes with same rigor
• Hazard analysis method and level of approval dependent on type of change.
Determine Hazard Level
• Examples of yes/no questions to determine the hazard level:– Does the change introduce a significant source of
energy (chemical, mechanical, thermal, electrical)?
– Does the change result in any increase of toxic, flammable, or reactive material?
– Does the change significantly increase the potential for personnel exposure to a hazardous material?
Determine Potential Severity
• Examples of yes/no questions used to determine potential severity level:– Could the change take the process outside the safe
operating envelope?
– Does the change significantly alter the heat and material balance?
– Does the change introduce new molecules?
Risk MatrixSeverity of Change
Low High
Degree of Low Risk Level 1 Risk Level 2
Hazard High Risk Level 3 Risk Level 4
Risk Level Type of Safety Review Authorization
1 Simple Checklist Shift Supervisor
2 What-if Checklist Unit Supervisor
3 FMEA or HAZOP analysis Area Supervisor
4 HAZOP with consequence analysis Plant manager
A successful MOC program is
dependent on ...
Management Support
• Vital element in success of MOC system
• Honor your commitment– if an employee follows the system and the
change is approved - then implement change!!
• Important to show full support so that employees understand the benefits and don’t feel like you don’t trust their judgement.
Stakeholder Involvement• Essential to keep
stakeholders informed throughout the MOC process.– will prevent them from
putting up “road blocks” later.
• Stakeholder communication can provide a fresh perspective.
Simplicity
• “A modest MOC system that is regularly used and works is much better than an elaborate, sophisticated system with an impeccable paper trail that is occasionally winked at, bypassed, or sometimes totally ignored.”– Roy E. Sanders
Lessons Learned
• Don’t focus solely on modifications.
• Don’t have unnecessarily tight equipment specifications.
• Applies to all process units, not just those containing flammable or toxic substances.
• Make sure there is easy access to documentation.
Lessons Learned (cont.)
• Save all records - both approved and disapproved.
• Make sure EVERYONE is aware of MOC program.
• MOC must address both types of risk - short term and long term.
Conclusions• Improper plant modifications have
been a major cause of chemical plant accidents.
• A formal method to deal with change will prevent future accidents from occurring.
• Change is unavoidable in industry– all organizations should have a MOC
program.