A project can have several, parallel, near critical paths; and some or all of the tasks could have 'free float' and/or 'total float'. An additional parallel path through the network with the total durations shorter than the critical path is called a sub-critical or non-critical path.
Indeed, the average person canât hold their breath for more than 30 seconds or so â and even someone in excellent health is gasping by two minutes. Sietas pictured at the start (left) and finish (right) of the new breath-holding record of 18 minutes and 16 seconds in a water tank. Most Japanese pearl divers, who dive deep without oxygen for their treasure, canât manage more than seven minutes.
It is rather boring and can be very dangerous though. If you're asking how long could someone hold their breath if they are forced to because of an emergency situation then 30 seconds and even that might be generous.