Abstract Another reaction sequence is employed to show the change in the superiority order. The previous sequence — employing five gases [C 2F 4(g), NF 3(g), CF 4(g), COF 2(g), SF 6(g)], was based on H 2O(g). The superiority order showed SF 6(g) to be non-RAP. The new sequence based on HF(g) employed H 2(g) for a double RAP of the same five gases. That sequence showed SF 6(g) to be the top RAP agent.