Which of the following is a factor used to convert absorbed dose to effective dose (EfD)?

• A. Tissue weighting factor
• B. Dose rate
• C. Exposure
• D. Shielding thickness

Answer: (A)

Efficient risk assessment uses how sensitive each tissue is to radiation. To get the effective dose from the absorbed dose, you apply a tissue weighting factor that represents each tissue’s relative risk contribution, and then combine those weighted doses across all tissues (taking into account radiation type with a weighting factor, which is typically 1 for X-rays). The tissue weighting factor is the essential multiplier that links absorbed dose to the overall effective dose because it accounts for which tissues are more or less susceptible to harm.

The other options don’t perform that conversion: dose rate describes how quickly the dose is delivered, exposure is an air-based quantity, and shielding thickness affects how much dose is reduced but isn’t used to convert absorbed dose into effective dose.