Particulate matter (PM) emissions from construction activities pose a significant health risk to both on-site workers and surrounding urban populations. Despite increasing awareness, the adoption of advanced digital technologies to support PM emission management remains limited. In particular, Digital Twin (DT) applications in this domain are still underdeveloped and lack dedicated frameworks to guide their design and deployment. This paper proposes a high-level conceptual framework for a DT system aimed at monitoring, managing, mitigating, and predicting PM emissions on urban construction sites. Building on established DT paradigms in the AECO sector and the research gaps identified in a prior systematic review by the authors, the framework is developed through the identification of key aspects across three main dimensions: (i) stakeholders and use cases, (ii) data acquisition from heterogeneous sources, covering both static and dynamic information, and (iii) system requirements, including functional and technical capabilities. The framework provides a foundation for future research, informing the development of DT architectures and supporting the implementation of responsive, sustainable, and health-conscious construction site management strategies in urban environments.