“Does one plus one exceed two?” The synergistic effect of Innovative City and Smart City pilots on work safety governance—evidence from a quasi-natural experiment

Work-safety governance is a fundamental pillar for aligning high-quality development with robust safety standards and serves as a critical safeguard for workers' rights to life and decent work. Utilizing panel data from 218 Chinese cities spanning 2008-2023 and employing a staggered difference-in-differences (DID) model, this study investigates whether the dual pilot programs for Innovative Cities and Smart Cities generate a synergistic effect, where "1 + 1 > 2," that enhances urban work-safety governance outcomes. The key findings are as follows: (i) The dual-pilot policy significantly enhances work-safety governance through synergy. Compared to non-pilot and single-pilot cities, dual-pilot cities experience an average reduction of 69.8 and 38.8 fatalities in work-safety accidents, respectively. Moreover, the "innovation-first" implementation sequence yields a notably stronger synergy than the "smart-first" pathway. (ii) Mechanism analyses reveal that the policy improves work-safety governance primarily via two channels: technological innovation (TI) and industrial upgrading (IU), with safety regulation (SR) positively moderating the policy's effectiveness during implementation. (iii) The spatial spillover effect of the dual-pilot policy follows a distance-decay pattern characterized by promotion in nearby areas, suppression in mid-to-far areas, and disappearance in distant areas. Specifically, the policy promotes safety governance within 800 km, exerts suppressive effects between 800 and 1,400 km, and its influence essentially vanishes beyond 1,400 km. (iv) Heterogeneity tests demonstrate that the dual-pilot policy's governance effects are more pronounced in non-resource-based cities, small- and medium-sized cities, and cities located in the central region. This study contributes new empirical evidence on the synergistic mechanisms of urban safety governance within a risk society context and provides valuable policy insights for constructing more efficient urban work-safety governance systems.