result of an asset reaching functional
failure ("F"), which is measured as the impact/significance on the
following two entities:
CoF is established through a criticality analysis
and expressed along a criticality
index along the vertical (y-axis)
of a risk matrix.
Ranking of Consequences
The severity of the consequences of failure are either
expressed as linguistic variables (low, medium, high) or numerical
Listed below is an example
of a four-tiered linguistic classification for CoF:
consequences would include matters such as loss of life and injury to
persons. "Critical" would include significant damage to the building
- Tier 1: "Catastrophic"
- Tier 2: "Critical"
- Tier 3: "Marginal
- Tier 4: "Negligible"
Types of Consequences
Listed below are some of the different types of
consequences of failure.
P h y s i c a l:
F i n a n c i a l:
- Greater nuisances from noise, vibrations, smells, etc. that affects the quiet use and peaceful enjoyment of the property.
- Increased outages associated with power supply, water supply, gas, and other utilities.
- Increased downtime and disruptions with essential services, such as elevators, etc.
- Reduced reliability of systems and assets.
- Collateral damage to finishes and substrates from water ingress and water escape conditions.
- Unsightliness that detracts from the exterior and interior aesthetic appearance of the building. (aesthetic deterioation)
- Accelerated deterioration of some assets requiring earlier renewal.
L e g a l:
- Increased costs
due to lack of planning, reactive/crisis planning, accumulation of
deferred maintenance, unnecessary repairs, shortened service lives,
greater project scopes, etc.
- Greater financial hardship through special levies, demand loans, etc.
- Diminished marketability of the suites due to stigmatization, etc.
- Lower resale value of the property.
- Inefficiencies in the use of energy, coordination of people and other resources
- Missed opportunities for leveraging economies of scale, etc.
- Waste and ground contamination
- Increased contingency allowances for substrate repairs
S o c i a l / p s y c h o l o g i c a l/ Communty:
- Potential for fines and penalties due to non-compliant conditions.
- Potential accidents and Injuries to owners, guests and invitees due to unsafe slip, trip and fall conditions.
- Increased insurance deductibles due to failure to mitigate
- Increased risk exposure to individual owners and the organzation from failure to do the necessary due diligence.
- Jeopardizing of warranties due to failure to meet duty of care
- Fire watch
Further discussion on the different types of
consequences can be found at failure
effects and maintenance
motivators and replacement
- Increased stress and frustration of individual owners/guests due to unresolved business and limited peace of mind.
- Potential for conflict between owners due to unresolved isssues, greater time at general meetings, etc
- Residents may have to vacate the premises during emergency repairs
Calculating Consequence Score
Included below are the three primary methods of calculating consequence scores, each with their own merits and limitations:
- Max consequence - find the consequence with the highest score
- Average Consequence
- Sum of Consequence
Weighting of Consequences
The consequences of failure are established by weighted analysis
of the following metrics
effects or maintenance
motivators and replacement
owners risk profile is expressed by attaching weightings to
each of the criteria. This may be established with the following:
Weightings will be affected by subjective bias of
persons who are making the evaluation of consequences. For example, an
engineering consultant will perceive the consequences of failure
associated with deferment of the washing of the exterior windows as
negligible while an owner who occupies one of the suites may consider
this to be higher.
Matrix of Consequences
- Roof failure = physical and financial (but not legal). consqueqnces are tier 2/3
- Fire alarm failure = financial and legal. consequences are tier 1/2
Listed below are some examples to help illustrate the application of
the CoF to different scenarios:
burst pipe that leaks into the building causing damage to interior
finishes [Opex] and flooding into the elevator shaft
[performance] would generally be
considered "critical" (Tier 2)
- The failure of a hot water recirculating
pump will result in loss of domestic water and may be considered
"marginal" (Tier 3).
failure of a roof membrane that leaks into the building and causes
significant disruption to the space users (Operations) and damage to
interior finishes The quantitative and qualitative expression of possible loss that considers both the probability that an event will occur and the consequence of that event. would be classed as "critical" (Tier 2).
canopy that is loose and could fall onto people entering the building
and injuring someone (safety), perhaps fatally would be classed as
"Catastrophic (Tier 1).
Listed below are some of the key steps in the assignment of CoF
rankings to events:
- Identify the asset (eg., roof)
- Determine the criticality of the assets (bounded?)
- Identify the failure modes (eg., blister
in membrane that leaks)
- Identify the failure effects (eg.,
- Classify the failure effect (eg.,
collateral damage is physical and financial)
- Assign a weighting to roof leaks (eg.,
- Assign a criticality score (eg., 70 out
- Establish a preservation strategy that
recognizes the probability of failure (PoF) over a given time horizon.
CoF is most essential for critical
assets and bounded
assets. and serves to provide data for a program of Risk-Based
decision making is at the heart of asset management and this requires
mindful consideration of the relationship between the probability of
failure (PoF) and the consequences of failure (CoF). The complexities
of these correlations can sometimes be captured on a risk matrix.
Fig. Consequences of Failure (CoF) represented on the vertical (y-axis)
of a criticality matrix (risk matrix).
I. Care is oblivious to the extraordinary events that can totally wipe
out his assets and upset the delicate order of things, such as force
majeure and acts of God.
array of some of the physical consequences of failure.
Fig. Risk matrix with tiered separation of the consequences of failure
Fig. I. Care spinning the wheel of misfortune to determine the consequences of deferred maintenance.
Fig. I. Care is trying to avert the cascading effect of one problem compounding another in his building.
Fig. I Care has opened up Pandora's Box and will now have to face all the consequences.