To maintain effective oxygen delivery, what should be checked before using a demand mask?

Ensuring a proper fit of the mask for sealing is crucial when using a demand mask to maintain effective oxygen delivery. A well-sealed mask ensures that oxygen is delivered directly to the user without any leaks, which is essential for optimal performance. If the mask does not fit correctly, outside air can compromise the oxygen concentration, reducing the effectiveness of the mask in delivering the necessary oxygen during emergencies.

The fit also affects the comfort of the user and their ability to breathe normally while using the mask. A mask that is too loose or improperly positioned may cause discomfort, leading to distractions or panic in critical situations, which could hinder the effectiveness of oxygen delivery. Thus, checking for a proper seal is a fundamental step prior to using a demand mask.