Smoldering Combustion Does smoldering combustion only occur in an environment where oxygen levels are low? Will it always transition into flaming combustion (whenever there is ample supply of oxygen?

Or can it keep smoldering even when there is an ample supply of oxygen?

Some smoldering areas in forests continue to smolder for years where there is an ample supply of oxygen -> it's open air.
If you're smoldering, you're generally not producing enough heat to vaporize anything except in a small local environment. Only the vaporized fuel will burn.