Which statement is true regarding SCBAs?

Self-Contained Breathing Apparatus (SCBA) are specifically designed to protect the wearer from environments that are oxygen-deficient or contain harmful contaminants. This is essential in various scenarios, such as firefighting, industrial incidents, and rescue operations, where the atmosphere may not be safe for breathing. SCBAs provide their own source of breathable air, allowing users to operate safely in potentially hazardous conditions.

The design and function of SCBAs ensure that they effectively deliver a reliable supply of clean air directly to the user, which is critical for maintaining safety in environments where oxygen levels could drop below safe limits (typically below 19.5% oxygen concentration). By maintaining adequate oxygen supply, SCBAs enable personnel to perform rescues and emergency operations without the risk of suffocation or asphyxiation.

In contrast, other choices do not accurately reflect the capabilities and applications of SCBAs. While SCBAs can sometimes be used in various contexts beyond just firefighting, their primary purpose is safety in oxygen-deficient environments, which makes the statement regarding their design for such atmospheres the most accurate.