What is the minimum length requirement for metal monuments?

The minimum length requirement for metal monuments being eighteen inches is established to ensure adequate depth and stability in the ground. This dimension helps prevent the monument from being easily displaced or damaged, which is crucial for maintaining accurate survey marks over time. Monuments serve as reference points in land surveying, and their durability is essential for the integrity of the survey data. An eighteen-inch length provides sufficient embedding in the ground, reducing the likelihood of movement caused by environmental factors such as erosion or frost heave. This standard is generally accepted in many surveying practices, ensuring consistency and reliability in the profession.