Description: In the article the evolution of an isolating means for protection of respiratory organs. Discussed projects and real samples, was developed for the Navy, fire service, mining and land forces. Special attention is paid to the work conducted in the German and Russian Empires before and during the First world war.
Keywords: gas Mask, respirator, toxic substances, oxygen breathing apparatus, a vicious cycle of fighting, Professor A. P. Pospelov. D. G. Levitsky, Professor N. D. Zielinski, Henry Draeger