The
classification of maintenance assets in relation to their criticality is
essential to helping maintenance management define its priorities.
The
classification of maintenance assets in relation to their criticality is
essential to helping maintenance management define its priorities.Risk Level
The risk level of an event is
characterized by its impact and likelihood of occurrence, usually, its
assessment is computed by a risk matrix that combines these two principles.
According to the graph, we can conclude that the risk is higher in the red area
with considerable impact and probability, lower risk on the green areas and
medium risk on the yellow.
Criticality assessment of assets
Sometimes the criticality of an
equipment is confused with the risk of having technical problems, but in
reality, the consequences of failure have to be taken into account. ISO 55000
suggests that a critical asset should be one that has the potential to have a
significant impact on the achievement of a company's objectives.
We can thus conclude that the risk
assessment of maintenance assets is not focused on pieces of equipment but
rather on its consequences for the company.
Need to assess the criticality of assets
There is no greater waste than using
our time and resources to do something that will not be used in the future.
For this reason, before starting the
analysis of the criticality of maintenance assets, one must have a notion as to
what this classification will be used for.
Critical asset classification can be
used for various purposes in maintenance, but it will depend on company's
policies and its management objectives. Some of the decisions that may be
sustained by asset risk classification are as follows:
• Elaboration
of an efficient maintenance plan according to the company's resources;
• Definition
of a predictive maintenance plan;
• Definition
of priorities when planning work/tasks;
• Elaboration
of a list of spare parts needed for critical equipment;
• Assets
in which a greater engineering effort will be made to improve reliability;
• Investments;
• Etc,
etc ...
Understanding the risk of events
As mentioned above, risks must be
assessed according to the consequences that an event may have for the company.
For example, if there
are two production lines in which one produces for the company's most important
customer every week of the year and the other works for other customers at a
lower frequency,then in
the classification of risk, the first line assets should always have a higher
evaluation than the second.
If the company has two compressors that
are redundant and, to meet its consumption needs, only one needs to be working,
then the risk is not very high. If there are two other compressors under the
same conditions, but they are ammonia compressors, the risk of a leak can bring
health issues, environmental issues and even credibility issues for the
company, therefore,
although a redundant system is in place, the risk s higher.
We can then conclude that, when the
risk of a potential failure in maintenance assets is assessed, taking into
account their consequences for the company, its impact on several aspects: production,
maintenance, health, environment, quality and more should be assessed.
Alongside with any area that may have a negative impact on the company.
Critical assets analysis
In order to begin an asset
classification process in relation to the consequences of a potential failure,
a multidisciplinary team of different areas of the company should be gathered
that can bring important input to decision making. For example maintenance,
production, safety, quality, etc.
The analysis should start by the elaboration
of an impact/probability risk matrix and define the areas that should be
evaluated as having an impact on the company (production, environment, health,
safety, legal compliance, company reputation, etc.). The probability can be
analyzed mathematically or taking into account the experience and history of
asset failure.
Asset analysis should not be done as a
list where assets will all be on the same level, which makes the process
time-consuming and confusing, but opt for a hierarchical analysis by
installation level.
The analysis must always be from the
higher to the lower level, and the classification of lower levels should always
be equal to or less than that of the higher levels. This definition will
structure and accelerate the analysis process, making it more efficient.
Strategy to reduce risk
After classification of their assets,
managers must define strategies to mitigate the risk of potential failures. An
example of a decision table may be as follows:
As a conclusion we understand that in
efficient maintenance, effort and resources must be distributed according to
the company's objectives, the classification of the criticality of its assets
is fundamental to decisions support and maintenance management organization.
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