How Long Can He Last Without Air

Today I want to try out how long the slave can last without air. Ive brought along a stop watch and sit down on his face right away - and start the stop watch! I sit on his face and smother him in different positions. Later I also try smothering him with my hands for a short time - while kneeling on his chest - dont want it to be to easy for the loser ;- Then the facesitting continues!