Home
Bookshop
Seminars/Webinars
Incidents
Management
Occupational Safety
Offshore Industries
Onshore Industries
PSM
Bow Tie Analysis
Emergencies
FMEA
HAZOP
HAZOP Team
Incident Analysis
Inherent Safety
MOC
Operating Procedures
PSSR
PHA
Process Safe Limits
SEMS
Technical Safety
Acronyms
/ Definitions
Annotums
Citations
Examples
Organizations
Privacy / Commercial
Site Map
Contact Us
|
|
|
|
The root cause of all accidents is uncontrolled change. Leaving aside sabotage and other malicious acts, all industrial
facilities are designed
and operated to be safe, clean and profitable - yet incidents continue to occur.
In every case, the fundamental cause of the incident is that someone, somewhere
lost control of the operation, i.e., they allowed operating conditions to deviate beyond their safe range.
|
Update January 2012. We have published the
third edition of the ebook
Management of Change.
Hence, the proper management of change is the foundation of all safety and accident prevention programs; an effective
Management of Change (MOC) creates an atmosphere of "no surprises". Likewise, the day-to-day lives of everyone associated with
that operation will flow more smoothly and productively when operations are stable. It is when
there are upsets and unexpected problems that managers are subject
to out-of-hours telephone calls from the plant, complaints from
unhappy customers and unsolicited offers of help from corporate
headquarters.
Because of its central role in assuring safety,
Management of Change is a critical component of all Process Safety
Management (PSM) programs.
The Meaning of the Word "Change"
It is imperative to clearly define the word "change" in the context of a Management of Change program. OSHA considers a
change that is not a "replacement in kind" as one that requires an
MOC review. However the term 'replacement in kind' needs further
definition. After all, as discussed below, all changes are 'not in
kind' if examined closely enough.
Some thoughts on the types of change that take place in a process facility are provided below.
Initiated Change
An initiated change occurs when someone, usually a manager or an engineer, decides that he or she would like to modify
the operation so that conditions move outside the current safe
operating range. The following are examples of initiated change:
-
A process engineer proposes an increase in reactor temperatures in order to increase production.
-
The operations manager plans to
manufacture a new grade of chemical using existing
equipment.
-
A chemist suggests the use of a new
additive to improve yields.
-
An operator requests that the logic of
a control loop on a distillation column be changed in order
to improve product quality.
-
A maintenance engineer proposes that
the size of a pump motor be increased in order to reduce the
number of times that the pump trips.
The key to all of these situations from a Management of Change point of view is that the person involved
proposes to operate the plant at conditions that have never been
experienced before. Hence, there is no direct operating
knowledge or experience as to what will happen following the
change. Therefore, changes of this type will generally need to
be analyzed carefully, often through use of a multi-discipline
hazards analysis team.
Reactive Change
A reactive change is one that occurs spontaneously; unlike initiated change a reactive change is not
created by a person's conscious decision. Corrosion is a common
example of a reactive change; a vessel or a pipe may be
gradually losing wall thickness without anyone knowing about it
until an unplanned incident, such as a leak from a pipe, occurs.
Organizational and personnel changes are
often reactive. For example, management may decide to eliminate
a night-shift position in the lab, not realizing that they
system has now "changed" and that safety-critical analyses may
not be available to the operations personnel.
Reactive changes cannot be effectively controlled by the Management of Change program because they occur by
themselves, not because someone wishes for them to occur.
Therefore reactive changes have to be through other elements of
the facility's Process Safety Management (PSM) program. These
elements include Equipment and Instrument Integrity, Process
Hazards Analysis and
Incident Investigation.
Overt Change
Reactive Changes can be either overt or covert. An overt change is one that is known about, and whose
consequences can be mitigated before an accident actually takes
place. For example, if an operator notes that a key variable such as a reactor temperature or a tank level is getting out of
control, he or she is witnessing an overt reactive change. If
allowed to continue, an accident may occur, so some sort of
action must be taken.
Overt change is often gradual and can be
controlled when detected. For example, if the facility has an
equipment integrity program to monitor changes in wall thickness
caused by corrosion then potentially critical situations can be
corrected before they result in a leak.
Overt, reactive changes can sometimes be identified if it is found that the operations or maintenance
personnel have developed "work-arounds" in response to a problem
that they are experiencing. The following are examples of such
work-arounds.
-
Operators start a certain compressor in a
non-standard manner because the way in which it is currently
done frequently causes electrical surges that upset
operations in other parts of the facility.
-
A warehouse worker suggests that spare parts
be stored in a different way because the current system had
led to a number of mix-ups, some of which could have led to
an accident.
-
A pipe fitter suggests that a certain nozzle
be made of a higher grade of steel. An investigation as to
why he made the recommendation reveals that the existing
system is suffering from excessive erosion, and that it has
to be repaired frequently. Failure of the nozzle identified
by the pipe fitter could lead to a release of hazardous chemicals.
Covert Change
A covert change is not known about before it "announces" itself - often quite suddenly. For example, if no one knows that a particular pressure vessel
is corroding, then the first indication of a problem will be when the vessel starts to leak. It is not generally possible to install safeguards
to identify covert, reactive changes because those changes are inherently unpredictable.
Covert changes sometimes occur to utility systems that serve more than one operating unit. Each operating unit may make properly controlled changes
to its
own equipment, not realizing that such changes are having a
system effect. For example, new equipment that has been
added to the facility over a period of years may have
created an unidentified overload of passive safety systems
such as the flare header and the closed drain system. In an
emergency, these overloaded safety systems may fail to
provide adequate protection. The changes in one area thus
have an impact on other areas.
Another example of covert change occurs if a
plant installs a new process that handles a highly toxic
gas. If there were to be a release, the gas could cross the
plant boundary and enter another plant that is owned by a
different company. This second plant may not have the
appropriate emergency response program to handle a release
of this gas.
In-Kind / Not-In-Kind Change
The phrase "not-in-kind" change is used
extensively in Management of Change literature, and has
already been referred in the discussion to do with the OSHA
standard. If an equipment item is to be replaced with one
that is functionally identical, i.e., if
the new item is built to the same specification as the old
one, then the change is "in-kind". Otherwise it is
"not-in-kind", and the MOC process has to be followed before
the change can be implemented.
The In-Kind/Not-In-Kind decision is
critically important. The most challenging aspect
of managing change is identifying that the proposed
modification is in fact a change.
An incorrect assumption that a proposed change is
not-in-kind could lead to the occurrence of a serious
incident. (The opposite scenario is less of a concern. If
the change is incorrectly determined to be not-in-kind, but
later turns out to be in-kind, then the only loss is that
some time has been wasted on unnecessary evaluation.)
Because of the criticality of this
decision, the supervisors and lead operators need to be
thoroughly trained on deciding whether a change should be in‑kind/not-in-kind, particularly since the choice of
in-kind change offers a tempting way of by-passing the whole
Management of Change process.
Unfortunately, the distinction between in-kind and not-in-kind changes is not as simple as it might
appear. In particular, there are two difficulties that must
be considered in the context of Management of Change, the
first of which is to do with circularity of meaning of the
following type:
-
Management of Change is needed
if the change is Not-In-Kind.
-
A Not-In-Kind change is one
where Management of Change is needed.
In other words, the terms "Management of
Change" and "Not-in-Kind" tend to be defined in terms of one
another.
The second difficulty to do with the
In-Kind/Not-In-Kind decision, noted above, is that all changes
are, when analyzed deeply enough, not-in-kind. Even if an
item of equipment is being replaced with a supposedly identical
spare, there will always be differences between the
replacement and original items. For example, the new
item will have been made by different people, at a different
time, possibly with different machinery. It may have been
stored for a different length of time, and may be installed
by different people, who have different levels of training
and experience from those who made the first installation.
When evaluated rigorously in this manner, all changes are
not-In-kind.
Generally, differences such as those just
described will not be significant, but small changes can
cause large accidents. On one facility, for example, a very
serious accident resulted when a supposedly in-kind
replacement gasket was inserted into a filter housing as
part of a routine operation. The new gasket leaked, and a
major fire ensued resulting in extensive equipment damage
and many weeks of lost production (fortunately no one was
injured). After the event it was determined that the new
gasket was not in fact identical to the old one, even though
all parties concerned had thought that it was. (A further
significance of this incident was that the uncontrolled
change occurred in the facility's warehouse - an area that
would not normally be considered when developing Management
of Change programs.)
Based on the above discussion, a replacement equipment item can be judged to be in-kind if it
meets the following criteria:
-
Same Specification
If the replacement item has the same technical specifications as the original, then it is
In-Kind. These specifications typically include
material(s) of construction, dimensions and weight.
-
Same Service
The service in which the item is
being used should not have changed. Process conditions,
including pressure, temperature and process materials, must
be the same as for when the original item was in service.
Also, the inspection and maintenance requirements
should not have changed.
-
Procedural Replacement
The replacement should be a routine operation - one carried out by operations and
maintenance technicians with a consistent level of training
and experience. Either the item is replaced as part of a
preventive maintenance program, or experience has shown that
it wears out within a known period of time and then must be
replaced. If the original item is failing inexplicably, then
simply putting in a replacement part is not sufficient. There must be some reason for the system failures
- they
could be occurring because the system has changed in some
undetected manner. Hence use of the MOC system is
required.
-
Replacement - Not Improvement
The new item should be a genuine replacement - not an improvement on the old one.
If the purpose of the replacement is to upgrade the
operation in some manner, then the change is not in-kind.
For example, if a new vendor is used to replace an identical
part to the same specification as the old part, the change
may not be In-Kind. After all, the reason for using the
new vendor is that management wanted to make a change to the
system (probably to reduce costs or improve system
reliability). Therefore, there must be some difference
between the old and the new products in order to explain why
the new vendor was chosen. For this reason, decision
to change a vendor or a supplier should generally be
validated using the Management of Change process.
The Change Process
An eight-step process for implementing a Management of
Change (MOC) process is illustrated in Figure 1 below.
This structure attempts to address all the issues that need
to be covered when evaluating and recommending change. Even
if a different system is being used, each of the topics
described in this eight-step approach should be covered by
whatever Management of Change system is being used.
Figure 1
Eight-Step MOC Process
Section A - Initiator Request
The change process starts when someone identifies a problem that needs to be corrected, or believes
that there is a better way of operating the process. That
person is referred to here as the
Initiator.
Usually, the initiator will be a manager, a supervisor or an engineer. However, the Management of Change system should be
open to all; anyone should feel free to propose changes that
they believe will make the facility safer, cleaner and more
profitable.
The ultimate success of the Management of Change system depends on people being willing to suggest
changes. There is little value in having a high quality
change review process if it is never used or if it routinely
bypassed.
Section B - First Review
Following the initiation of the Management of Change process, the next step is to carry out
the First Review, which should be informal and relatively
unstructured. It is sometimes referred to as the "red face" test.
Section C - Detailed Evaluation
Up to this point, the change process has involved only a few people, and has been relatively
informal. If the proposed change still seems to have merit
it can now be submitted to the Management of Change system,
where it will be evaluated by a team of people representing
different disciplines and specialties. This is the detailed
evaluation step.Section D
- Selection and Approval
Once the proposed change has been thoroughly
evaluated, and a list of possible recommendations prepared,
facility management must select what is considered to be the
best choice, and formally approve that choice.
Before a change can be implemented, it must
be formally approved and accepted by the plant management.
This approval is necessary to meet the requirements of the
process safety regulations. The approval also serves as a
formal record should there ever be an accident in which the
implicated as a possible cause. In practice, if the detailed
evaluation in Section C was carried out thoroughly this
formal acceptance step should not take long, and should be
little more than a formality.
Section E - New Limits / Process Safety Update
Once the change has been approved, new safe operating limits are defined and the engineering
documentation can be updated. All persons that are
affected by the new values must be informed. They must
also be trained in what to do if the new limits are
exceeded.
Section F - Notification
Before the change is actually implemented, all affected parties should be notified. This
is usually done via e-mail.
The notification process is distinct from training; it concerns those people who have some peripheral involvement with the
consequences of the change, but who are not directly
affected by it.
Section G - Implementation
Finally, the change can be implemented.
Section H - Follow-Up
Once the change has been implemented, there should be a follow-up to make sure that all precautions and preparations were
handled properly.
|