Estimate Effective Dose from DAP with This Simple Tool

 

Estimate Effective Dose from DAP with This Simple Tool

This tool provides an estimated effective dose (in millisieverts, mSv) based on the dose area product (DAP) value—commonly expressed in units like Gy·cm² or cGy·cm². It supports DAP-to-mSv conversions for various types of radiographic examinations.

Please note: the result is an estimation, not an exact measurement. The calculation uses standardized conversion coefficients derived from ICRP Publication 103 and further detailed in the following reference:

Wall BF et al. Radiation risks from medical x-ray examinations as a function of the age and sex of the patient. Report HPA-CRCE-028, Health Protection Agency (2011). Available at: www.hpa.org.uk

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How It Works: An Example

Radiograph type: Abdomen AP
DAP value: 2 Gy·cm²
Conversion coefficient (Abdomen AP): 0.18 mSv per Gy·cm²

Calculation:

Effective dose = DAP × Conversion coefficient  
               = 2 Gy·cm² × 0.18 mSv/(Gy·cm²)  
               = 0.36 mSv

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Available Radiograph Types and Conversion Coefficients

This tool includes conversion factors for a wide range of standard projections, including:

• Head: AP, PA, Lateral

• Cervical Spine: AP, Lateral

• Shoulder: AP, Axial

• Chest: PA, Lateral

• Thoracic Spine: AP, Lateral

• Lumbar Spine: AP, Lateral, Lumbosacral joint Lateral

• Abdomen: AP

• Pelvis and Hips: Pelvis AP, Single Hip AP, Both Hips AP

• Lower Extremities: Femur AP, Femur Lateral, Knee AP, Knee Lateral

• Foot: Dorsi-plantar, Oblique

These coefficients allow for quick and consistent estimations of patient dose across routine diagnostic radiology procedures.