This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Stenhousemask. Woodcut of Stenhouse's mask from The VelvetLined Gas Mask of John Stenhouse from Edward Youmans' ClassBook of Chemistry New York published in Armed Forces Chemical Journal accessed at brinkster html PDold Particulate respirators People wearing respirators
Page 2023 Free-images.com. All images are Public Domain