...
The piston must be able to supply enough force at its operating pressure to break the shear pins with a ?x 2x safety factor. According , which is the safety-critical guideline presented by NASA. [5] According to standards established by the Aerospace Corporation, there must be a minimum 1.5 design burst factor. [4]
...
[4] Aerospace Corporation, Operational Guidelines for Spaceflight Pressure Vessels
[5] NASA, Structural Design Requirements and Factors of Safety for Spaceflight Hardware