In 1940, James D. Hardy, Harold G. Wolff and Helen Goodell of Cornell University introduced the first dolorimeter as an instrument used to measure pain threshold and pain tolerance. Using the "dol" as a unit, with the name coming from the Latin word for pain, dolor, the physicians created a 0 to 10.5 dol scale.
There are several kinds of dolorimeter that have been developed, by applying steady pressure, heat, or electrical stimulation to some area, or move a joint or other body part and determine what level of heat or pressure or electric current or amount of movement produces a sensation of pain.
Even though there is no conclusive medical evidence, it is said that a human body can bear only up to 45 dol of pain. Yet when giving birth, a mother feels up to 57 dol of pain, similar to 20 bones getting fractured at the same time.