Which of the modes is more protective?

Pressure demand mode is recognized as a more protective method because it provides a higher level of safety in environments where airborne contaminants, such as lead, are present. This mode ensures that air is supplied to the user only when they inhale, creating a positive pressure environment in the respirator. This design helps prevent contaminants from entering the mask, offering better respiratory protection against hazardous substances.

In contrast, continuous flow mode constantly delivers air, which might reduce the effectiveness of the respirator by allowing for potential leaks. Standard air mode and short-duration mode do not provide the same level of protection as pressure demand, particularly in situations where exposure to lead dust is a concern. The ability of pressure demand mode to maintain a positive pressure within the mask creates a more secure and protective barrier against harmful particles.