Clark Grave Vaults
A Clark grave vault will withstand the earth's load above it after 90% of the metal has been lost. This graphic shows how long Clark vaults will last in the ground before undergoing a 50% metal loss. Clark vaults are also double-welded inside and out for added strength, rigidity, and overall longevity.
Note that the Clark Metal Protection Index (MPI) allows you to compare the amount of time the vault will protect its contents underground. An increase of 1 in the MPI index is equal to 33 years of protection; for example, a vault with an MPI of 2 will protect for 66 years before undergoing a 50% metal loss.
