A range pole, which may also be called a lining pole, is a pole painted with alternating stripes of different colors in consistent widths used often to site measurements. The tool may be a common one for surveyors, where the colors for the stripes are usually red and white or red and yellow. The colors are picked based on their visibility. One end of the pole will typically have either a pointed tip or gripping shoe to aid in standing it on edge. Longer range poles may be equipped with a tripod or stand.
In typical use by a surveyor, the range pole may be either stuck in the ground or held in place over a point, often by an assistant. The surveyor then observes the pole through a surveying instrument. The most common reasons the range pole is employed are to calculate unknown angles, elevations, and distances with the aid of other equipment. The surveyor notes where a point in the distance falls among the consistently-spaced stripes on the pole, and by inputting this information and the known distance to the range pole into a formula can calculate unknown measurements.
Some modern range poles may be equipped with global positioning system (GPS) hardware. In such a case, the pole acts as an antenna for the GPS unit, with the receiver at the top. These GPS antenna poles allow greater accuracy in surveying. Some versions of modern range poles are also telescoping.
The range pole may be made of wood, metal, fiberglass, or any composite, but rigid material that will resist bending is ideal. In certain applications, however, non-conductive materials may be preferred for the sake of safety. Strong materials that can be easily manufactured as tubes are well-suited for telescoping range poles. Even if the pole itself is made of another material, a common choice for the pointed tip is metal, as it may be easier to stick into the ground and is unlikely to wear as quickly as other materials.
Regular range poles are commonly 8 feet (approximately 2.4 meters) long and 0.5 to 1 in. (about 1.25 to 2.5 cm) in diameter. Collapsible range poles vary in length, but may extend past 20 feet (approximately 6 meters), with the longest poles intended for use with GPS units. The increased length allows the antenna poles to extend the GPS unit over potential obstructions, such as trees. A common width for the stripes is 1 foot (about 30.5 cm).