Background

Diagnostic radiology is a major contributor to radiation exposure from man-made sources. Dose Area Product (DAP) is widely used to estimate patient radiation dose and assess associated risks. Establishing effective dose values and comparing them with international reference levels is essential for dose optimization.

Objective

To estimate effective dose (ED) in common digital radiographic examinations using DAP measurements and to compare the results with international dose reference levels.

Materials and Methods

This prospective study was conducted on 350 adult patients undergoing 27 routine radiographic examinations at UCMS and GTB Hospital, New Delhi. DAP values were recorded using a KermaX® DAP meter attached to a digital radiography system (Definium-8000, GE). Patient demographic parameters and exposure factors (kVp, mAs, FFD) were documented. Effective dose was calculated using standard conversion coefficients. Statistical analysis was performed using mean ± standard deviation and one-sample t-test.

Results

The mean DAP values (Gy•cm²) were 0.13 ± 0.09 for Chest-PA, 0.43 ± 0.22 for Abdomen-AP, 0.47 ± 0.39 for Pelvis-AP, 0.50 ± 0.30 for Lumbar-AP, and 0.88 ± 0.44 for Lumbar-Lateral examinations. Corresponding mean effective doses (mSv) were 0.02 ± 0.01, 0.07 ± 0.04, 0.066 ± 0.05, 0.11 ± 0.06, and 0.29 ± 0.041 respectively. The estimated effective doses were significantly lower than international reference levels reported by Hart et al. (2005) and comparable with other published studies. Statistical analysis showed significant differences (p < 0.002).

Conclusion

Effective doses estimated using DAP in digital radiography were generally lower than established international reference levels. The study highlights the role of modern digital systems in dose reduction and provides baseline data for establishing Diagnostic Reference Levels (DRLs) in the Indian population.