What does it mean for a respirator to be positive pressure?

A respirator being described as having positive pressure indicates that the air pressure inside the respirator exceeds the ambient air pressure outside. This design is important for ensuring that the airflow is directed outward, preventing hazardous external air from entering the respirator. Positive pressure helps to maintain a supply of cleaner air for the wearer, which is crucial in environments where contaminants are present.

The effectiveness of a positive pressure respirator lies in its ability to keep contaminants out by creating an internal pressure that is greater than that of the outside atmosphere. This is particularly vital in protective equipment used for hazardous materials or in environments with poor air quality.

In contrast, options denoting lower internal pressure or inefficiency do not characterize positive pressure respirators correctly. Negative pressure scenarios would describe situations where air can be drawn in, thereby allowing potentially harmful particles or gases to enter the breathing space. Therefore, the defining feature of a positive pressure respirator is its design to exceed external ambient pressure, ensuring safety and protection for the user.