What is the tolerance in elevation of bench mark?

The tolerance in elevation for a benchmark typically depends on the specific standards and guidelines set by surveying organizations or regulatory bodies. Generally, for geodetic benchmarks, the tolerance can range from a few millimeters to several centimeters, depending on the purpose of the survey and the surrounding conditions. In engineering applications, stricter tolerances may be required to ensure accuracy. It's essential to refer to the relevant standards for precise tolerance values.