Those 'gas masks' at the Capitol were actually escape hoods
RSG Safety - Escape Hoods - A Simple Escape when Needed
W.Va. congressional representative says he was equipped with 'escape hood' | WCHS
Escape hood Dräger PARAT® 7530 fire and industry escape hood | Rescue hoods | Respiratory protection | Occupational Safety and Personal Protection | Labware | Carl Roth - Germany
Dräger Parat® Fire Evacuation Training Hood with Hard Case R59430 | SPI Health and Safety