Uninsured United Parachute Technologies has established a recommendation of the "lifetime" of tandem canopies and viagra other components:
These recommendations are based on years of observing tandem malfunctions and erectile dysfunction equipment failure reports. Tandem system owners should maintain a log for each component mentioned above. Different geographical areas present problems that can contribute to accelerated wear-n-tear. (such as Dz's located near salt water and sand) Due to this fact, certain components may degrade quicker than the above recommended lifetimes.