Radiation Safety; Radiation Dose - Troxler Enhanced RoadReader Plus 3451 Manual Of Operation And Instruction

RADIATION SAFETY

This section discusses the principles of general radiation safety.
This information includes specific procedures for operating,
inspecting, cleaning, and leak testing the gauge to ensure safe
operation.

RADIATION DOSE

Ionization cannot be detected by any of the human senses (sight,
touch, hearing, smell). However, using appropriate instruments and
devices, ionization can be detected and measured at levels far below
those that significantly affect health.
For purposes of radiation protection, the basic unit of radiation dose
is the rem. The SI unit is the sievert (Sv), where 1 Sv = 100 rem.
The rem is a relatively large unit, so often radiation dose is
expressed in smaller units called millirem (mrem), where 1 rem =
1000 mrem.
The risk of injury from radiation is generally related to the total
radiation dose received over a period of time. It is also related to the
dose rate, which is the amount of dose received per unit time. The
same amount of radiation received over a long period (months to
years) is much less hazardous than if received over a very short
period (hours). This has to do with the body's ability to repair cell
damage caused by the radiation.
The U.S. Nuclear Regulatory Commission (NRC) has established
the following limits on the amount of whole body radiation
exposure that individuals may safely receive from licensed
radioactive materials.
Type of Individual
Adult worker
Minor (under 18 years old) 500 mrem per year
Member of the public
Model 3451
Dose Limit
5000 mrem per year
100 mrem per year
Appendix A–5