Which of the following can indicate an oxygen deficient atmosphere?

An oxygen-deficient atmosphere is specifically characterized by low levels of oxygen, which can pose serious health risks, including impaired cognitive and physical functions, loss of consciousness, and even death in severe cases. The presence of low oxygen levels is a direct indicator of an environment where there may not be enough breathable air for safe operation, especially in confined spaces.

To safeguard personnel, monitoring for low oxygen levels is essential in environments where this condition might arise, such as in storage tanks, chemical plants, or other confined spaces where air circulation may be limited. This is why recognizing low oxygen levels as an indicator of an oxygen-deficient atmosphere is crucial for ensuring safety protocols are followed.

In contrast, the other options mentioned, such as clanging sounds, high humidity levels, and excessive heat, do not directly inform about the presence of oxygen levels. They may signify other potential hazards or conditions but do not provide critical information about the availability of oxygen in the environment.