Certified Respiratory Therapist Practice Exam

A leak at the gas outlet after attaching a yoke connector to an E-size cylinder typically indicates that the gas outlet bushing is missing. The bushing plays a crucial role in ensuring a tight and secure fit between the cylinder and the yoke connector. Without it, there is a gap that allows gas to escape, resulting in a noticeable leak.

In this context, a defective cylinder could also be a source of leaks; however, the specific situation described—where a yoke connector has just been attached—strongly suggests that the absence of the bushing is the immediate cause of the leak. The cylinder's size is appropriate since the scenario discusses an E-size cylinder, thus ruling out size-related issues. Lastly, back pressure from the regulator may create problems, but is less likely to directly cause a leak at the gas outlet when the connection is first made. This reinforces the idea that the missing gas outlet bushing is the most plausible explanation for the leak observed in this scenario.