 John Voltathan and Rick Stanton had been braving Thamelong's narrow, murky passageways for several days, laying out guide ropes and searching for signs of life. On Monday, the two men finally reached Pattaya Beach, but there was nothing. They continued onwards into the darkness. Then a few meters further, they found an air pocket. Wherever there was airspace, we surfaced. No doubt we smell, John told the BBC. It's a standard procedure for such rescue operations.