CST Level 1 Land Surveyor Certification Practice

Which abbreviation stands for 'Height of Instrument' in regular leveling notes?

1. BS

2. FS

3. HI

4. Elev

The correct answer is: HI

The abbreviation 'HI' stands for 'Height of Instrument' in regular leveling notes. This term is crucial in surveying as it refers to the height at which the instrument is situated above the reference point being used for leveling measurements. The HI is determined by adding the height of the instrument above the ground to the known elevation of the point where the instrument is set. It is essential for calculating the elevation of the points being surveyed because it forms the basis for establishing a relationship between the instrument's position and the surveyed points. Understanding the HI is fundamental, as it allows surveyors to accurately determine the difference in elevation between various surveyed points. When performing leveling, knowing the Height of Instrument is key to maintaining precision and ensuring that the calculations lead to reliable results in surveying projects. In contrast, the other abbreviations relate to specific measurements in leveling but do not denote the height of the instrument itself. For instance, 'BS' stands for 'Back Sight,' which is the first reading taken on the staff after leveling to establish the HI. 'FS' stands for 'Fore Sight,' which is the reading taken on the staff at the point being determined for elevation. 'Elev' typically indicates 'elevation' but does not specify the height of the instrument.