Generally speaking, a diving certification was required for recreational freediving. As Li Du and the others free-dove for work, they were not required to have a diving certification.
Max, who was a very responsible diving instructor, strongly demanded the four of them to get their diving certifications since getting one was not difficult and required only three days.
"With my guidance, you guys won't even need three days," Max told them confidently. "If you guys learn diligently, two days will be enough to get the diving certification."
Just like a driving test, Australia's diving test was also separated into different components, namely the theory test and practical test.
The two days that Max spoke of was for passing the theory test. Although the practical test required a longer time to pass, they could take the opportunity while they were training in water to pass the test requirements.