The fracture of the ribs must take 3 months before you can do heavy work, because when doing heavy work, whether it is carrying or lifting something, the thorax must hold its breath to exert force, and the force on the thoracic rib cage is more serious. If the rib fracture is not fully stabilized, it cannot be subjected to gravity and cannot do heavy work. It must take more than 3 months for the fracture to grow into a visible scab before the fracture end is completely stable and will not heal due to heavy work. If the fracture is not yet stable and heavy work is done, it may cause the fracture to fracture and misalign again and lead to deformed healing.