Which device is used for immediate, on-site measurement of exposure and may be read directly?

Which device is used for immediate, on-site measurement of exposure and may be read directly?

• A. Geiger-Mueller detector
• B. TLD
• C. Pocket ionization chamber
• D. Film badge

Answer: (C)

Immediate, on-site dose readouts come from a pocket ionization chamber, also called a pocket dosimeter. It uses a tiny air-filled chamber where ionizing radiation creates ions. An electric field collects the charges, and the stored charge corresponds to the exposure; the device is read right there, giving a direct dose reading since the last reset. This real-time feedback is why it’s favored when workers need to monitor their dose during a shift. In contrast, a Geiger-Mueller detector mainly signals the presence and rate of radiation but doesn’t provide a direct, user-friendly dose value. Thermoluminescent dosimeters and film badges record exposure but require processing in a lab to obtain any usable dose reading, so they can’t be read immediately on-site.

Immediate, on-site dose readouts come from a pocket ionization chamber, also called a pocket dosimeter. It uses a tiny air-filled chamber where ionizing radiation creates ions. An electric field collects the charges, and the stored charge corresponds to the exposure; the device is read right there, giving a direct dose reading since the last reset. This real-time feedback is why it’s favored when workers need to monitor their dose during a shift.

In contrast, a Geiger-Mueller detector mainly signals the presence and rate of radiation but doesn’t provide a direct, user-friendly dose value. Thermoluminescent dosimeters and film badges record exposure but require processing in a lab to obtain any usable dose reading, so they can’t be read immediately on-site.