The seatpost is tested to the latest ISO 4210 standard for Racing & Mountain Bicycles. These standards typically specify "Static Strength" tests (i.e. one-time application of force) as well as "Fatigue" tests (i.e. repeated application of force) for different bicycle components. 
We also run our own independent tests to better understand lifespan which typically involve cycling well beyond the specifications in the ISO 4210 standard.