To investigate the arc ignition characteristics of bridge wire electro-explosive devices （EEDs） under DC excitation and predict the arc ignition safety threshold， the simulated charge method was exploited to calculate the cross-sectional electric field strength between the foot-wire and shell of bridge wire EEDs， following a scaled experiment for EEDs to solve unknowns in the electrical breakdown model， which is the electrical breakdown coefficient between the foot-wire and shell of EEDs， leading to a quantitative criterion and arc ignition prediction model. Results indicate that when the laboratory temperature is around 25° and the air pressure is atmospheric pressure， the distance between the foot-wire and shell of bridge wire EEDs significantly influences the arc ignition threshold，and the shorter the foot-shell distance is， the lower the arc ignition threshold is. The relative error between the measured breakdown voltage and the calculated results from the predictive model does not exceed 3.3%. Furthermore， the relative error between the foot-shell breakdown coefficient simulated in COMSOL and the calculated results from the predictive model is within 1%， verifying the model"s accuracy. This research provides a reliable tool for predicting arc ignition safety thresholds， potentially enhancing the design and safety of EEDs.