EAAI Journal 2026 Journal Article
A diffusion-based visual monitoring framework for detecting human behaviors and hazards in chemical plants
- Ligang Chang
- Binhan Xu
- Xinyu Zhang
- Jiayue Wang
- Tianyu Shi
- Rui Guo
- Yanhui Du
A key challenge in chemical plant safety is that unsafe human behaviors often coincide with physical hazards. Although intelligent monitoring systems could address this by detecting both, their development is hindered by the scarcity of annotated data. This study presents a generative visual monitoring framework built on Stable Diffusion 3. 5 to synthesize diverse safety-critical scenarios under limited data conditions. To construct multimodal training data, Chat-Unified Visual Representation (Chat-UniVi) is employed to automatically generate text descriptions for six categories of unsafe human behaviors and two categories of hazards collected from the internet, along with chemical plant background scenes. These text–image pairs serve as structured inputs for contrastive pretraining and subsequent optimization of the Stable Diffusion 3. 5 model. The diffusion model is subsequently optimized through three stages: contrastive pretraining enhances semantic discrimination, Low-Rank Adaptation (LoRA) fine-tuning improves feature alignment, and meta-learning strengthens generalization across multiple risk categories. A hierarchical prompt-template design enables controllable image synthesis across camera viewpoints, worker behaviors, and hazard types, while a depth-guided Conditional Control Network (ControlNet) module enhances realism in safety-critical regions. The generated data are then used to train a lightweight You Only Look Once version 11–nano with a Stage-2 Feature Pyramid layer (YOLOv11n-P2) detector, enabling robust recognition of unsafe human behaviors and multi-scale hazards in complex chemical plant environments. Experimental results demonstrate that this diffusion-based framework provides a scalable and practical artificial-intelligence-driven solution for proactive safety monitoring in chemical plants. The dataset and implementation code are publicly available on our project repository.