You are in a tank wearing a breathing apparatus and you desire to return topside. How many tugs of the lifeline mean "Take up slack"?

Correct Answer: Option C — 3

Standard tank entry safety signals utilize standard lifeline pulls defined in OSHA and marine safety protocols: 1 pull means 'Are you alright?' or 'Stop', 2 pulls mean 'Give more line' or 'Lower', 3 pulls mean 'Take up slack' or 'Stand by to haul up', and 4 pulls mean 'Help me out'.