Question 63Safety & Environmental - 1st Asst/Chief

The correct answer is A) breathing apparatus should always be used. The reason this is the correct answer is that when a cargo tank has not been certified as gas free, it is unsafe to enter without proper personal protective equipment, including a breathing apparatus. Petroleum vapors can be toxic and flammable, and can displace oxygen, posing a serious risk to anyone entering the tank without the appropriate safety gear. This is a critical safety requirement under the regulations governing cargo tank entry and is not dependent on factors like weather or time spent in the tank. The other answer choices are incorrect because they suggest it may be safe to enter the tank without a breathing apparatus, which is not the case when the tank has not been certified as gas free.