Richins' Rule (updated 9/23/98)
I have developed a simple formula, called the "Richins Rule" or "Effort Factor" which incorporates both the distance to be traveled (in miles) and the elevation to be climbed (in feet) into a single formula for estimating the total amount of time (in hours) required to reach your backcountry destination. This rating system provides the climber/hiker/backcountry skier with a method of estimating approach and climbing times of a particular peak or route.
The Richins Rule or effort factor described below is a refinement of Naismiths Formula. The Scottish climber W.W. Naismith in 1892 developed a means of estimating route times in the Scottish Highlands and English Lake District by taking into account both the distance to be walked and the elevation to be climbed. His formula was: Time in minutes = (12 x distance in km) + 0.1 x elevation (in meters). This formula assumes that one can hike at a rate of three miles per hour and gain 2,000 feet an hour!!! In snow, over rough terrain with a heavy pack, at the much higher elevations of the Sierra Nevada and Colorado Rockies, the Naismith formula is not particularly applicable. For more information on the Naismiths Formula link to Paul Kennedy's Homepage--Mountain Ramblings.
The Richins Rule corrects for some of these differences and is as follows: Time in hours = (distance hiked in miles/2 mph) + (elevation gain in feet/1,000 feet per hour).
The Richins Rule or Effort Factor assumes that a hiker/skier in good shape with a 35-40 pound pack can average, over the course of a day, about 2 miles an hour on level terrain, and climb at a rate of 1,000 feet per hour. As an example, the summit of Mount Tallac is about 3 miles and a climb of 3,300 feet. Applying the formula to this example, the Effort Factor is: (3 miles/2 miles per hour) + (3,300 feet/1,000 feet per hour) = 1.5 +3.3 = 4.8 hours. In this example, it will take about 5 hours to climb to the summit of Mount Tallac. Of course, the snow conditions, the altitude of the peak, the weight of ones pack, as well as the condition and strength of each hiker/climber/skier are major factors not reflected in this equation. On shorter trips, such as in this example, a hiker/skier in good condition will easily beat the predicted time. Whereas on longer, harder trips the same hiker/skier may take longer than the predicted time as a persons rate of progress slows over the course of a long day.
The formula can be adjusted to match your speed and endurance in the mountains by changing the assumptions. Maybe assuming 750 feet of elevation gain per hour is more representative of your climbing speed, or 2.5 or 3.0 miles per hour your hiking pace. Adjust the formula accordingly.
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