Kecelakaan kerja masih menjadi isu penting di tempat kerja, termasuk di PT X, sebuah perusahaan yang bergerak di bidang telekomunikasi. Salah satu upaya preventif yang dilakukan adalah pelatihan keselamatan dan kesehatan kerja (safety training) bagi pekerja lapangan. Penelitian ini bertujuan menganalisis efektivitas safety training dalam meningkatkan pengetahuan K3 pada pekerja lapangan PT X tahun 2025. Penelitian menggunakan mix method dengan desain pre-eksperimental (One Group Pre-Test Post-Test) pada 55 peserta pelatihan. Data kuantitatif diperoleh melalui pre-test, post-test, dan kuesioner kepuasan, sedangkan data kualitatif dikumpulkan melalui observasi dan telaah dokumen. Analisis statistik dilakukan dengan paired sample t-test, sementara data kualitatif dianalisis secara deskriptif berdasarkan model evaluasi CIRO (Context, Input, Reaction, Outcome). Hasil: Hasil penelitian menunjukkan adanya peningkatan nilai rata-rata pengetahuan K3 dari 87,64 pada pre-test menjadi 92,73 pada post-test atau naik 5,81% dengan perbedaan yang signifikan (p < 0,05). Seluruh peserta (100%) mencapai nilai di atas Kriteria Ketuntasan Minimal (KKM) sebesar 70. Rata-rata kepuasan peserta terhadap pelatihan mencapai 4,14 (kategori tinggi), dengan penilaian tertinggi pada kompetensi instruktur. Evaluasi aspek konteks dan input menunjukkan bahwa pelatihan sesuai kebutuhan, difasilitasi dengan baik, dan disampaikan oleh instruktur kompeten. Secara keseluruhan, safety training dinyatakan efektif dalam meningkatkan pengetahuan K3.

Workplace accidents remain a major concern, including at PT X, a company engaged in the telecommunications sector. One preventive effort implemented is occupational health and safety (OHS) training for field workers. This study aims to analyze the effectiveness of safety training in improving OHS knowledge among field workers at PT X in 2025. A mixed-method approach was used with a pre-experimental design (One Group Pre-Test Post-Test) involving 55 training participants. Quantitative data were collected through pre-tests, post-tests, and satisfaction questionnaires, while qualitative data were gathered through observation and document review. Statistical analysis was conducted using the paired sample t-test, and qualitative data were analyzed descriptively based on the CIRO evaluation model (Context, Input, Reaction, Outcome). Results showed an increase in the average OHS knowledge score from 87.64 (pre-test) to 92.73 (post-test), representing a 5.81% improvement, with a statistically significant difference (p < 0.05). All participants (100%) achieved scores above the minimum passing criteria (≥ 70). The average satisfaction score was 4.14 (high category), with the highest rating in instructor competence. Evaluation of the context and input aspects indicated that the training was relevant, well-facilitated, and delivered by competent instructors. Overall, the safety training was effective in enhancing workers’ OHS knowledge.