What is the primary purpose of a Hand Level?

The primary purpose of a Hand Level is to keep measuring tape horizontal on sloping ground. This device is a simple tool used by surveyors and contractors to ensure that measurements taken on uneven terrain are accurately aligned horizontally. When using a hand level, an operator can hold it at a specific point while keeping the bubble within the vial centered, confirming that the line of sight is level. This is crucial when measuring distances for laying out construction or assessing site conditions since having a horizontal reference is important for ensuring accuracy when marking points or laying foundations.

The other options focus on different tools or functions that are not performed by a hand level. For instance, measuring vertical angles pertains to the use of a theodolite or similar instrument. Determining the weight of construction materials would require scales or load cells, while marking elevation changes is typically done with more advanced surveying equipment to provide precise level readings.