Question 61Safety & Environmental - 1st Asst/Chief

The correct answer is D) all of the above. The condition of a fuel tank certified as "Safe for Men" and "Safe for Fire" can change due to any of the factors listed in the answer choices. A change in ambient temperature, a product leak into the tank, or the presence of muck, sludge, or scale that can give off additional vapors can all affect the tank's certified condition. These factors can alter the tank's atmosphere and potentially make it unsafe, necessitating re-evaluation by a marine chemist. The other answer choices are incorrect because they only address a single factor, while the certified condition of the tank can be impacted by multiple variables as stated in the correct answer.