Iron dust explosion characteristics with small amount of nano-sized Fe2O3 and Fe3O4 particles

•Two methods were used as the explosion criteria to determine the MEC.•A simplified flame propagation model was used for the iron dust explosion.•The explosion residues were found to grow up 4–6 times of the iron dust for the first time.•The secondary acceleration of dP/dt of iron dust explosion was found for the first time.•Fe3O4 has a better inerting effect than Fe2O3 for iron dust explosion moderation.