Electronic Theses and Dissertation

Proteksi radiasi dalam bidang radiologi merupakan hal krusial mengingat paparan berulang sinar-x berpotensi menimbulkan efek biologis berbahaya akibat ionisasi jaringan tubuh. material pelindung konvensional berbasis timbal (pb), meskipun efektif, membawa permasalahan berupa bobot yang berat serta risiko pencemaran lingkungan, sehingga mendorong pencarian material alternatif yang lebih aman dan berkelanjutan. penelitian ini bertujuan mengkaji potensi komposit bermatriks epoksi berpengisi serbuk cangkang kerang tiram yang kaya akan kalsium karbonat (caco₃) sebagai material alternatif pelindung sinar-x melalui pengujian densitas dan radiation protection efficiency (rpe). sampel komposit dengan ketebalan 0,5 cm dibuat dengan variasi ukuran partikel pengisi yang lolos ayakan 40, 60, 80, 100, dan 200 mesh, kemudian diuji pada rentang tegangan 40-100 kvp menggunakan multimeter sinar-x raysafe. hasil penelitian menunjukkan bahwa densitas dan rpe meningkat seiring mengecilnya ukuran partikel pengisi. sampel dengan partikel terkecil (lolos 200 mesh) mencatat densitas tertinggi sebesar 1,62 g/cm³ dan rpe tertinggi pada seluruh variasi tegangan, yakni 67,7% (40 kvp); 55,6% (60 kvp); 49,3% (80 kvp); dan 42,9% (100 kvp). berdasarkan hasil penelitian, komposit ini berpotensi untuk dikembangkan sebagai material pelindung alternatif radiasi ramah lingkungan meski masih memerlukan optimasi untuk menyamai performa timbal konvensional. kata kunci: pelindung radiasi sinar-x, material pelindung alternatif, komposit epoksi, cangkang kerang tiram

Radiation protection in radiology is critically important, as repeated exposure to X-rays can cause harmful biological effects through the ionization of human tissue. Conventional lead (Pb)-based shielding materials, while highly effective, present significant drawbacks including excessive weight and environmental toxicity, driving the search for safer and more sustainable alternatives. This study investigates the potential of an epoxy-matrix composite filled with oyster shell powder, a natural source rich in calcium carbonate (CaCO₃), as an alternative X-ray shielding material, evaluated through density and Radiation protection efficiency (RPE) measurements. Composite samples of 0.5 cm thickness were fabricated with filler particle size variations passing through 40, 60, 80, 100, and 200 mesh sieves, and subsequently tested across a tube voltage range of 40–100 kVp using RaySafe X-ray multimeter. Results demonstrate that both density and RPE increase consistently with decreasing filler particle size. The finest particle sample (passing 200 mesh) achieved the highest density of 1.6890 g/cm³ and the highest RPE values across all tested voltages: 67.7% (40 kVp), 55.6% (60 kVp), 49.3% (80 kVp), and 42.9% (100 kVp). Based on the findings of this study, the composite shows potential as an environmentally friendly alternative radiation shielding material, although further optimization is still required to match the shielding performance of conventional lead. Keywords: X-rays shielding materials, alternative shielding materials, epoxy composite, oyster shells