What should be done if a gas mask is difficult to clear?

When a gas mask is difficult to clear, the recommended action is to attempt to clear it again using the outlet valve. This is essential because the primary function of the gas mask is to protect the wearer from harmful agents by ensuring a proper seal and airflow. The outlet valve allows exhaled air to escape, which can help to clear the mask of any fogging or contaminants.

It's important to maintain a clear field of vision and ensure effective respiration while wearing the mask. Reattempting to clear the mask using the outlet valve can often resolve the issue without needing to remove the mask, which would expose the wearer to the hazards the mask is designed to mitigate. In situations where visibility and air quality are crucial for safety and tactical effectiveness, attempting to clear the mask first is a prudent course of action before considering removing or discarding it.