Risk Quantification

7. How did NASA decide what is or is not an acceptable risk?

NASA identified and evaluated hazards through a formalized hazard reduction process as described in the NASA Handbook, NHB5300.4. The process required that hazards be determined for probability and credibility. In order to ensure that the standards within NHB5300.4 were adhered to, a Senior Safety Review Board was established for overseeing the risk assessment process. The process allowed for a certain amount of risk to be allowed as long as it was acceptable. To determine whether or not a hazard was an acceptable risk, NASA used a Safety Classification System, which was a qualitative system rather than a quantitative system. This was due to the high cost associated with gathering enough data to be able to use a quantitative system. A quantitative system would also have created additional paperwork due to the technical requirements for a space shuttle. However, a quantitative system should have been developed and utilized. The risk classification system NASA used consisted of five levels, as seen below.

8. What was NASA’s risk response plan?

NASA was able to transfer and reduce some of its risk, however, due to the scope of the program, they were also forced to retain some of the risk. One key aspect to this approach to risk response is the need for a solid control plan. NASA did not have a complete control plan, which cased a lot of issues as the shuttle development program progressed. They did use their risk classification system (as discussed in question 7) and waivers (as discussed in question 11) as part of their risk response plan, but it wasn’t nearly as developed as it should have been.

9. How should they have handled risks that weren’t quantified?

As NASA conducted more and more space flights, they were gathering data that could have been used