Light output is proportional to the radiation absorbed. These devices measure alpha, beta, gamma and slow neutron sources. Engineered Controls Administrative Controls Engineered Controls Engineered Controls are the primary means of controlling radiation exposure. Particulates that are large enough will settle out of air. Thus, distance will reduce the likelihood of exposure to radioactive materials released from an operation.
Radiation levels decrease with the square of distance.
As shown in Figure 4, a person at one unit of distance from a source will have four times more exposure to radiation than a person who is located at two units of distance from a source of radiation. Reducing radiation levels with shielding is another form of protection. Different forms of radiation are affected by shielding more than others. The ability of a specific material to attenuate radiation varies with the form of radiation. For example, to some extent air attenuates low energy beta waves but it has little effect for other forms of radiation.