A simple quality control tool for assessing integrity of lead equivalent aprons

Abstract

Background: Protective lead or lead-equivalent (Pbeq) aprons play a key role in providing necessary shielding from secondary radiation to occupational workers. Knowledge on the integrity of these shielding apparels during purchase is necessary to maintain adequate radiation safety. Aim: The aim of the study was to evaluate the lead equivalence in aprons based on simple quality assessment tool. Materials and Methods: 0.25 mm and 0.5 mm lead and lead-free aprons from 6 manufacturers were assessed using a calibrated digital X-ray unit. The percentage attenuation values of the aprons were determined at 100 kVp using an ionization chamber and the pixel intensities were analyzed using digital radiographic images of lead apron, copper step wedge tool, and 2 mm thick lead. Results: Mean radiation attenuation of 90% and 97% was achieved in 0.25 mm and 0.5 mm lead or lead-free aprons respectively. The pixel intensities from 0.25 mm Pbeq apron correspond to 0.8–1.2 mm thickness of Cu while 0.5 mm Pbeq aprons correspond to 2.0–2.8 mm of Cu. Conclusion: Pixel intensity increased with increase in the thickness of copper step wedge indicating a corresponding increase in lead equivalence in aprons. It is suggestive that aprons should be screened for its integrity from the time of purchase using computed tomography (CT), fluoroscopy, or radiography. It is recommended that this simple test tool could be used for checking lead equivalence if any variation in contrast is seen in the image during screening.

Keywords

• attenuation
• copper step wedge test tool
• lead equivalent aprons
• pixel intensity