What is the consequence of failing to check the oxygen content in a tank prior to vapor control operations?

Checking the oxygen content in a tank prior to vapor control operations is crucial for safety. If the oxygen levels are too high, there is a significant risk of explosion or fire. Flammable vapors can accumulate in confined spaces, and when mixed with oxygen, they create an explosive environment. The presence of oxygen at unsafe levels can lead to ignition sources triggering a combustion event, making it imperative to assess and manage the oxygen content before proceeding with operations.

The other consequences listed might have their importance, but they do not address the immediate and severe safety risk associated with improper oxygen levels in relation to vapor control operations. For instance, while cargo leakage, increased vapor pressure, or loss of cargo quality are serious issues, they do not pose the same immediate and catastrophic threat to personnel and the environment as the risk of explosion or fire. Ensuring safe oxygen levels is a foundational step in preventing such hazards.