https://www.usa.gov/copyrighted-government-workshttps://www.rawpixel.com/image/3577841
Gas, Gas, Gas!
Recruits of Charlie Company, 1st Recruit Training Battalion, shake their heads during chemical warfare defense training June 3, 2014, on Marine Corps Recruit Depot Parris Island, S.C. The recruits shook their heads and performed other exercises to prove their gas masks worked despite vigorous activity. (U.S. Marine Coprs photo by Cpl. Octavia Davis/Released). Original public domain image from Flickr
Public DomainFree CCO U.S. Government image for Personal and Business use