What is a key safety precaution before entering a confined space like a tank?

Conducting air quality tests is a crucial safety precaution before entering a confined space such as a tank. This is because confined spaces can present numerous hazards, including low oxygen levels, the presence of toxic gases, or flammable vapors. By performing air quality tests, workers can ensure that the atmosphere inside the space is safe for human occupancy. This testing typically measures the levels of oxygen, as well as harmful substances that could pose health risks, such as carbon monoxide or hydrogen sulfide.

Ensuring the tank is dry, while important, does not address atmospheric safety issues. Even if a tank appears dry, hazardous gases can still be present. Removing all electrical connections may reduce the risk of ignition from sparks, but it does not guarantee that the atmosphere inside the space is safe. Having emergency rescue teams on standby is a vital safety measure, but it is a secondary precaution that does not prevent accidents or hazardous situations from occurring before entry. Therefore, conducting air quality tests addresses the primary concern of ensuring a safe environment before any personnel enter a confined space.