NCEES Principles and Practice of Surveying Practice Exam

What is the allowable accuracy for an ALTA/NSPS Survey?

1. 0.05 ft + 30 ppm

2. 0.07 ft + 50 ppm

3. 0.10 ft + 100 ppm

4. 0.03 ft + 20 ppm

The correct answer is: 0.07 ft + 50 ppm

The allowable accuracy for an ALTA/NSPS survey is established to ensure a high standard of precision necessary for these detailed land boundary surveys, typically required for real estate transactions. The correct answer indicates that the allowable accuracy is 0.07 feet plus 50 parts per million (ppm). This standard reflects the requirement that land surveys must be sufficiently accurate to delineate property boundaries clearly. The inclusion of both a fixed component (0.07 feet) and a variable component (50 ppm) accounts for the potential for larger variances over greater distances. For every 1,000 feet of distance measured, an additional 50 ppm contributes to the overall allowable error, making this approach comprehensive in terms of accuracy over significant distances. By having this specific accuracy standard, ALTA/NSPS surveys can ensure reliability and reduce disputes regarding property lines, which is critical in the context of real estate and property development. It aligns the survey's outcome with professional expectations and legal requirements, enhancing the integrity of the survey results.