Question 638 Deck Safety

70% to pass

The atmosphere in a tank is too lean if it is _______________.

A capable of supporting combustion because the hydrocarbon content is above the UFL (Upper Flammable Limit)
B capable of supporting a fire once started
C incapable of supporting combustion because the hydrocarbon content is below the LFL (Lower Flammable Limit)
D not safe for ballasting
AI Explanation

The correct answer is C) incapable of supporting combustion because the hydrocarbon content is below the LFL (Lower Flammable Limit). In a tank, the atmosphere is considered too lean if the hydrocarbon content is below the Lower Flammable Limit (LFL). This means there is insufficient fuel present to support combustion, making the atmosphere incapable of supporting a fire. The other options are incorrect because A) refers to an atmosphere that is too rich, and B) and D) do not accurately describe a too-lean atmosphere.

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