In research that could lead to better gas mask filters, scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have been putting the X-ray spotlight on composite materials in respirators used by the military, police, and first responders, and the results have been encouraging. What they are learning not only provides reassuring news about the effectiveness of current filters in protecting people from lethal compounds such as VX and sarin, but they also provide fundamental information that could lead to more advanced gas masks as well as protective gear for civilian applications.