“At an after-school meeting, Hitler Youth don gas masks as part of their military training.” 1938. (via USHMM Artifact Gallery)

“Grenadiers from an unidentified regiment model the latest gasmasks…”, c. WW1 (by drakegoodman)

The Illustrated London News, December 11th, 1915.  

Canine Gas Mask, c. WW1. 

Australian Infantry, Ypres c. 1917.  

German Sentry in Gas Mask, c. 1915 (by drakegoodman)

Bavarian Artillery Officer and Gas Mask, c. WW1 (by drakegoodman)

“Commercial postcard depicting German troops preparing to assault enemy positions”, c. WW1 (by drakegoodman)

“Prussian unteroffizier wearing a newly issued Gummimaske” (by drakegoodman)

Early model “Gummimaske”, January 1916 (by drakegoodman)

Medics, c. WW1.  By drakegoodman