Iowa Code § 355.5: Measurements.

1. Measurements shall be made with instruments and methods capable of attaining the required accuracy for the particular problem involved.

2. Measurements as placed on plats shall be in conformance with the capabilities of the instruments used.

3. In a closed traverse the sum of the measured angles shall agree with the theoretical sum by a difference not greater than thirty seconds times the square root of the number of angles.

4. Distances shall be shown in decimal feet in accordance with the federal definition of a foot at the time the survey is performed.