A slam-shut safety assembly configured to provide redundant safety shutoff in a gas distribution system. The slam-shut safety assembly includes a valve body, a first slam-shut safety device coupled to the valve body, and a second slam-shut safety device coupled to the valve body. The valve body has an inlet, an outlet, and defines a flow path extending between the inlet and the outlet. The first slam-shut safety device is configured to block the flow path at a first position responsive to an overpressure condition or an underpressure condition. The second slam-shut safety device is configured to block the flow path at a second position responsive to the overpressure condition or the underpressure condition.