What type of dosimeter measures background radiation in TLD programs?

The control dosimeter is specifically designed to measure background radiation within TLD (Thermoluminescent Dosimeter) programs. Its primary role is to ensure that any radiation exposure measured in the field can be accurately compared to a baseline that accounts for the inherent background radiation in the environment. By utilizing a control dosimeter, facilities can observe and account for environmental influences on the readings obtained from personnel dosimeters.

In the context of TLD programs, which are used to measure ionizing radiation exposure, the control dosimeter remains in an unexposed area, serving as a reference point. This helps in identifying any exposure that might not be related to the individual's activities but rather due to background radiation. Other types of dosimeters mentioned, such as neutron dosimeters and whole body or extremity dosimeters, serve different purposes related to specific types of radiation or body areas and do not function in the same capacity as a control dosimeter for assessing background radiation levels.