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Considering ways in which a product could potentially fail is a crucial part of the design process.  All products must be designed such that they are both safe and reliable for use and any potential dangers must be addressed in the design phase.  The table below shows the primary ways in which the leaf blower studied for this report could potentially fail as well as the probable consequences, severity, causes, likelihood of occurrence, design safeguards, detectability of failure, recommendations for improvement and responsibility for making changes.  The values assigned for severity, likelihood of occurrence and detectability (S, O, and D respectively) are based on the tables found in Dieter and Schmidt's 'Engineering Design'.  The risk priority number (RPN) is simply the product of these numbers and can be used to assign a priority to potential failures in order to organize the redesign process.

! Assembly/Parts !! Failure Mode !! Consequence of Failure !! S !! Causes of Failure !! O !! Safeguards !! D !! RPN !! Recommendations !! Responsibility  

| Electric Motor and Wiring || Blown Fuse || Inoperable || 7 || Short circuit || 3 || Coated wire || 4 || 84 || None || N/A

| Electric Motor and Wiring || On/Off Switch Broken (Plastic fracture prevents operation) || Inoperable || 7 || Broken mechanism due to fatigue or misuse || 4 || Sliding design does not experience substantial fatigue || 4 || 112 || None || N/A

| Electric Motor and Wiring || Power cord worn || Potential shock hazard, may be inoperable || 8 || Cord worn by frequent twisting and bending || 5 || Flexible cord coating, longer cord is more flexible, wires also coated independently of cord || 2 || 80 || Plug directly into case with no wire; use wireless power source || Design Engineer

| Blower and Vacuum Attachments || Air concentrator locking tab broken || Unable to use air concentrator || 3 || Overuse leading to fatigue failure || 5 || None || 2 || 30 || Consider different locking mechanism || Design Engineer