How would you identify safety concerns when listening for engine noises with a stethoscope?

To identify safety concerns when listening for engine noises with a stethoscope, first ensure the vehicle is in a secure position, ideally with the engine off and cooled down to prevent burns. While the engine is running, listen for irregular sounds such as knocking, grinding, or hissing that may indicate issues like bearing wear or exhaust leaks. Pay attention to the volume and frequency of the noises, as abnormal sounds can signal potential safety hazards. Additionally, avoid placing the stethoscope near moving parts to prevent injury.