How is the rad related to the gray?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
radiation measurement
Figure 1: (A) A simple equivalent circuit for the development of a voltage pulse at the output of a detector. R represents the resistance and C the capacitance of the circuit; V(t) is the time (t)-dependent voltage produced. (B) A representative current pulse due to the interaction of a single quantum in the detector. The total charge Q is obtained by integrating the area of the current, i(t), over the collection time, tc. (C) The resulting voltage pulse that is developed across the circuit of (A) for the case of a long circuit time constant. The amplitude (Vmax) of the pulse is equal to the charge Q divided by the capacitance C.
The rad and the gray are both units used to measure the absorbed dose of ionizing radiation.12
The gray (Gy) is the standard unit within the International System of Units (SI), defined as the absorption of one joule of energy per kilogram of matter. The rad, which stands for "radiation absorbed dose," was defined as the amount of radiation that releases 100 ergs of energy per gram of matter.21
In 1975, the gray replaced the rad as the official unit because the rad was not coherent with the SI system. The two units are related by the following conversion:12
While the gray is the internationally recognized standard, the rad remains in use specifically within the United States.1