Statistical Analysis of Major Accident Reports and Development of a Real-time Detection Model for Portable Ladder and Safety Helmet

이동식사다리 중대재해 통계 분석 및 이동식사다리와 안전모 실시간 탐지 기계학습 모델 개발

  • Choi, Seung-Ju (Department of Safety Engineering, University of Ulsan) ;
  • Jung, Kihyo (School of Industrial Engineering, University of Ulsan)
  • 최승주 (울산대학교 안전보건전문학과) ;
  • 정기효 (울산대학교 산업경영공학부)
  • Received : 2020.12.03
  • Accepted : 2021.03.04
  • Published : 2021.03.31


The leading source of occupational fatalities is a portable ladder in Korea because it is widely used in industry as work platform. In order to reduce victims, it is necessary to establish preventive measures for the accidents caused by portable ladder. Therefore, this study statistically analyzed injury death by portable ladder for recent 10 years to investigate the accident characteristics. Next, to monitor wearing of safety helmet in real-time while working on a portable ladder, this study developed an object detection model based on the You Only Look Once(YOLO) architecture, which can accurately detect objects within a reasonable time. The model was trained on 6,023 images with/without ladders and safety helmets. The performance of the proposed detection model was 0.795 for F1 score and 0.843 for mean average precision. In addition, the proposed model processed at least 25 frames per second which make the model suitable for real-time application.


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