AUTHOR=Li ChunYa , Wang Jianhua , Luo Bingfeng , Yin Tubing , Liu Baohua , Lu Jianfei TITLE=SD-YOLOv5: a rapid detection method for personal protective equipment on construction sites JOURNAL=Frontiers in Built Environment VOLUME=Volume 11 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/built-environment/articles/10.3389/fbuil.2025.1563483 DOI=10.3389/fbuil.2025.1563483 ISSN=2297-3362 ABSTRACT=With the rapid growth of urbanization, construction sites are increasingly confronted with severe safety hazards. Personal protective equipment (PPE), such as helmets and safety vests, plays a critical role in mitigating these risks; however, ensuring proper usage remains challenging. This paper presents SD (Small object detection and DilateFormer attention mechanism)-YOLOv5s, an improved PPE detection algorithm based on YOLOv5s, designed to enhance the detection accuracy of small objects, such as helmets, in complex construction environments. The proposed model incorporates a dedicated feature layer for small target detection and integrates the DilateFormer attention mechanism to balance detection performance and computational efficiency. Experimental results on the CHV dataset demonstrate that SD-YOLOv5s achieves an average precision (AP) of 93.7%, representing an improvement of 2.8 percentage points over the baseline YOLOv5s (AP = 90.9%), while reducing the model’s parameter count by up to 14.6%. These quantitative improvements indicate that SD-YOLOv5s is a promising solution for real-time PPE monitoring on construction sites, although further validation on larger and more diverse datasets is warranted.