Taxonomic Categorization of Individual Risks

The CRM process involves three distinct taxonomies, a condition/departure taxonomy, an asset taxonomy, and a consequence taxonomy. To the extent that different risk issues have elements in common, these commonalities can be identified by classifying each element according to the appropriate taxonomy. It may then be possible, when deciding on an appropriate risk management response to the identified risks, to craft individual responses that simultaneously address all or most of the elements within a given taxonomic category.

Figure 46 and Figure 47 show example condition/departure and asset taxonomies, respectively. Such taxonomies are established at CRM initiation and should be maintained and updated over the course of the project. In order for taxonomies to be useful in identifying cross-cutting risks, taxonomies of a given type should be uniform across the scope over which cross-cutting risks are a concern, e.g., the program or project. The consequence taxonomy can be derived directly from the requirements tree for the program/project, since, by definition, the consequence of interest with respect to a risk issue is its effect on the likelihood of meeting the performance requirements.

Figure 47. Example Asset Taxonomy

Taxonomies are subject to modification over time as risks are identified that suggest revisions to the categories, further partitioning of categories, or the addition of new categories. Because they integrate elements of risk that cross organizational lines, they should be maintained by the project organization. However, the project must interact with all the organizational units within it in order to ensure that the taxonomy includes all issues of importance.

When entering an individual risk into the risk database, the CONDITION, DEPARTURE, ASSET, and CONSEQUENCE should be categorized according to the appropriate risk taxonomy. The CONDITION and DEPARTURE can each be categorized according to the departure taxonomy; the ASSET can be categorized according to the asset taxonomy; and the consequence can be categorized according to the consequence taxonomy. In each case, the taxonomy is entered at the top and navigated to progressively lower levels by determining which of the nodes at the next lower level best describes the item to be categorized. This process is iterated until either the lowest level along the particular path followed is reached, or until none of the nodes at the next lower level adequately apply to the item. In the latter case, the item is categorized in the ―Other‖ node below the last applicable node.

Over time, items may accumulate in ―Other‖ nodes throughout the risk taxonomies. For this reason, the taxonomies should be periodically reviewed and enhanced as needed to provide appropriate categories for the items. Because the taxonomies are used to communicate risk characteristics throughout the relevant units of the NASA hierarchy (e.g., all units working under a given Program unit), modifications to the taxonomies must be coordinated among the stakeholder units and kept uniform throughout.

Figure 48 illustrates the structure of a risk statement and the application of departure and asset taxonomies to the departure and asset, respectively.

Figure 48. Risk Statement Structure and Taxonomies

The yellow box below provides an example of how the conditions and departures from a set of individual risks defined in the Identify step of CRM may be assigned to a condition/departure taxonomy. While the individual risks used in this example are summarized in the table within the yellow box, complete risk statements and narrative descriptions for them may be found in Appendix G.

The example shows how the first attempt to fit the individual risks within the initial taxonomy may lead to the conclusion that the structure does not contain a sufficient number of categories to serve the purpose. The result is that the initial taxonomy is modified as needed (usually by a combination of expansion and rearrangement) to accommodate the individual risks without sacrificing its breadth. The final taxonomy and the assignment of the individual risks to the taxa are presented in tabular form in the example for compactness. However, a graphical form similar to Figure 46 and Figure 47 would also be appropriate.

The individual risks listed in the first table in the yellow box and described in Appendix G were selected as examples because each has some unique feature that distinguishes it from the others. For example, Risks 4(a) and 4(b) illustrate how an institutional risk, when expressed in one form, can also be a project risk when expressed in another form. Both have the same condition and departure event, but in one case the affected asset and resulting consequence are related to Center objectives and in the other case related to project objectives. The example illustrates that it is often difficult to unlink institutional and project risks, but if an institution does not manage its risks/resources well, projects can fail.

Departure Asset Cost Schedule Technical

An

Individual

Risk

Sample Departure Taxonomy Sample Asset Taxonomy

Safety

Condition Consequence

•Cause for concern

•Evidence RIDM O bj ec tiv es H ie ra rc hy … … …… ……

Planetary Science Mission Example: Development and Use of a Condition-Departure Taxonomy

During the initialization of CRM, the nine individual risks listed in the table below were identified and classified by condition, departure, asset, and consequence.

Num-

ber Title Condition Departure Asset Consequence

1a Planetary

contamination Knowledge of planet’s atmosphere is limited Higher-than- expected density causing spacecraft burn-through Spacecraft Planetary contamination 1b RCS in-flight

damage Knowledge of planet’s atmosphere is limited Higher-than- expected density causing RCS damage RCS Inability to achieve circular orbit 2 Pu238

availability The supply of Pu is low and Congress has not approved funds for processing

Cost of Pu may

increase drastically Electrical power / RTGs Funding exceeded 3 Thrust

oscillations Launch vehicle thrust oscillations near resonance frequency of payload Stresses may exceed design limits for instrumentation Scientific

instrumentation Loss of scientific data 4a DMS

institutional risk

Vendor for the DB querying utility will no longer support it

Utility may become nonoperational or obsolete Document Management System Inability to meet data management needs of the Center 4b DMS project

risk Vendor for the DB querying utility will no longer support it

Utility may become nonoperational or obsolete

Communications within the Project

Delay of launch date 5 Valve effect on mass margin Valve type in RCS susceptible to corrosion Replacement valve may be significantly heavier RCS Failure to meet mass requirements 6 Atmospheric

sensor TRL Atmospheric sensors are at TRL 2 and must reach TRL 8 prior to integration

The sensors may be unavailable or late

Scientific

instrumentation Failure to meet delivery date 7 Video sensor

stray light Another mission had degraded video due to stray light

Stray light may enter science package

Video system Unacceptable loss of data quality

An attempt was made to assign these individual risks to categories in the condition-departure taxonomy of Figure 46, but it was found that many of them did not fit naturally. As a result, the condition-departure taxonomy was modified to provide a better means for classifying these individual risks. The result is shown in the table below:

(Continued) Level 1

Category

Level 2 Category Level 3 Category Risks

External Departures Political Economic Public Relations Acts of God Other Programmatic Departures Institutional Resource Issues Budget Resources Schedule Resources

Info Tech & Mgmt Resources 4(a, b) Facility and Equip. Resources

Other Human Resource Issues Design Staffing Software Staffing Manufacturing Staffing Product Assurance Staffing Research & Analysis Staffing Launch Support Staffing Flight Operations Staffing Other

Subcontractor & Supplier Issues

Requirement Flow-down Supplied Item Defects Coordination Timeliness Other Material Resource Issues 2 Other

When more individual risks were added later on, inspection of the results revealed that they tended to congregate under two categories:

1) Programmatic departures  institutional resource issues  information technology & management resources

2) Technical departures  induced operational environments  loading & heating This observation helped the project allocate its resources more effectively.