ALARP – As Low as Reasonably Possible.

For anyone with any experience with risk management this is one of the key terms used to make a decision about applying risk mitigations.  It is used when going beyond a certain point (cost/weight/performance), open to definition by every company, that the resulting cost/performance of the product no longer makes fiscal sense.

Consider this example, attempting to develop an airplane where every passenger is in a seat that can detach from the airplane with a parachute, breathing apparatus and flotation device.  It would improve the passengers odds of surviving a mid-air incident, but the added weight and complexity would increase the power required to fly the plane, increase the size for all of the support mechanisms, and likely result in fewer passengers being carried.

Would airlines invest in such an airplane?   The reality of course is commercial air travel is incredibly safe, with no loss of life accidents in the USA in over 5 years.  This is a case where applying As Low As Reasonably Possible to a design makes sense both from a safety and business sense.

USE THE LOGIC ON ANY COMPLEX PROBLEM
The same logic can be applied to any complex system, what is the trade-off for addressing every risk no matter what the level, versus producing a product that offers a benefit to the users?  In cases where ALARP is applied on a project we’ll also be looking for senior management buy-in.

Making the decision to use ALARP can have a negative connotation and lead people to believe that the concern for users is not a priority.  So it is critical that senior management buy-offs on the plan, which will require a detailed case for taking this step.  Not just the risk management plan but an analysis that demonstrates the risk is as low as reasonable, the impact /risk of failures  versus the benefit of moving forward with the project. Example arguments can include this may be the only means of providing a medical treatment and without it more people could lose their lives than be at risk for a failure.

ALARP can be useful when moving into areas with a high return versus the higher risk of not addressing all mitigations.

Bio of Paul J. Kostek

Paul J. Kostek is a Principal of Air Direct Solutions, a systems engineering/project management consulting firm. He works with companies in defining system architecture, system requirements, interface definition, verification planning, risk management and software development standards. Paul received his BS from the University of Massachusetts, Dartmouth.   Paul works in a range of industries including: aerospace, defense, medical device and e-commerce.

Paul is a long-time volunteer with several professional engineering societies including IEEE, AIAA, SAE, INCOSE and PMI.  He also writes for the CERM.