Page 242 - Pipeline Risk Management Manual Ideas, Techniques, and Resources

Service interruption-impact factor 10/219
Operator error (Section B) 12 pts module. This is done through the determination of consequence
A higher chance for operator error due to the presence of auto- severity based on the pipeline surroundings.
matic valves near customers and relief valves in this section. Note that a high potential cost of a pipeline failure would be
addressed in the assessment of the pipeline surroundings in the
SectionA total = 15 + 20+ 11 +20+242+20+ 15 + l6= 359 basic risk assessment model (leak impact factor). Those
Section B total = 355 points implied costs (damages, injuries, etc.) are not repeated in this
module, even though they are legitimately an aspect ofthat par-
Reactive interventions are next evaluated. For Section A, it is ticular type of service interruption.
felt that system dynamics allow early detection and notification Some customers can incur large losses if interruption occurs
of any of the excursions that have been identified. The volume for even an instant. An example of this is an electric power gen-
and pressure of the pipeline downstream of Section A would eration unit that uses natural gas to fire turbines. Upon interrup-
allow an adequate response time to even a pipeline failure or tion of fuel to the turbine, all power generation might stop.
valve closure in Section A. Percentages are awarded for early Restarting such an operation is often a hugely expensive under-
detection (30), notification where the customer impact is taking. This is due to the complexity of the process. Many vari-
reduced (IO), and training (8). These percentages apply to all ables (temperature, pressure, flow rates, equipment speeds,
excursion types and, hence, increase the overall score based on etc.) must be simultaneously brought to acceptable points,
the difference between actual and maximum scores. Therefore, computers must be reprogrammed, safety systems must be
SectionA scores48% ~(540-359)+359 =446pointsinupset reset, etc. A similar situation exists for a petrochemical pro-
score. cessing plant. If the feedstock to the plant (perhaps ethane,
Early notification is not able to provide enough warning for propane, or crude oil) is interrupted for a long period, the plant
every excursion case in Section B, however. Therefore, reactive must shut down. Again, costs to restart the operation are often
interventions will only apply to those excursions that can be enormous. Many operations that are this sensitive to service
detected, namely, those occurring upstream of Section B. For interruption will have redundant sources of product that will
the types of excursions that can be detected in a timely manner, reduce the possibilities of loss.
product origin and equipment problems, percentages are In a residential situation, if the pipeline provides heating fuel
awarded for early detection (30), notification where the cus- under cold conditions, loss of service can cause or aggravate
tomer impact is reduced (IO), and training (8). Percentages are human health problems. Similarly, loss of power to critical
applied to the differences between actual and maximum scores. operations such as hospitals, schools, and emergency service
Potential for service interruption (upset potential) for Section B providers can have far-reaching repercussions. While electric-
is therefore the point total at far right, 361. This analysis shows ity is the most common need at such facilities, pipelines often
a much higher potential for service interruption for episodes provide the fuel for the generation ofthat electricity.
occurring in Section B (361 pts) as opposed to episodes in Some customers are only impacted if the interruption is for
Section A (446 pts). The impact factor would be calculated an extended period of time. Perhaps an alternative source of
next. A direct comparison between the two sections for the product is available for a short time, after which consequences
overall risk of service interruption can then be made: become more severe.
The most obvious cost of service interruption is the loss of
Intervention pipeline revenue due to curtailment of product sales. Other
Excursion t~pe udjustment Score costs include
Product ongin 30+ l0+8=48% 48%x(20- l5)+ l5= 17 Legal action directed against the pipeline operation
Product equipment NiA 20 Loss of some contract negotiating power
Pipeline dynamics 30 + 10+ 8 = 4X% 48% X (20 ~ 11) + 1 1 = I5 Loss of some market share to competitors
Other NIA 20 Loss of funding/support for future pipeline projects.
Pipeline failure 0 242
Pipeline blockages NIA 20
Pipeline equipment 0 15 Legal action, for purposes of this module, can range from
Operator error 0 12 breach of contract action to compensation for customer losses.
361 There is often a direct legal responsibility to compensate for
specified customer losses. In addition, there is an implied legal
responsibility that will no doubt be translated into compensa-
IV. Service interruption-impact factor tion for damages not directly specified by contracts. The possi-
bility and severity of legal action will depend on the legal
One of the real consequences associated with a pipeline outage system of the area and the degree of harm suffered by the cus-
is the cost of the interruption in service. Such an interruption tomer.
can occur through a pipeline leak, a product contamination In certain cultures and societies, a real but not-so-obvious
episode, or a loss of delivery pressure due to a non-leak event. cost of service interruption exists. This can be termed the
Because pipe failures are modeled as complete line ruptures in “sponsorship loss” of an interruption. Simply stated, the loss of
this assessment, most failures will lead to service interruptions service to certain customers can have more severe conse-
(from the failed section, at least), but as previously covered not quences than an equivalent loss to other similar customers.
all service interruptions are due to pipeline failures. Costs asso- The critical customer often has a degree of power or influence
ciated with pipeline failure and spilled product are indirectly over the pipeline operation. If this customer becomes hostile
assessed in the basic risk model and the optional environmental toward the operation, consequences such as loss of funding or