The appearance of the air weapon on the battlefields required major states to find with the utmost urgency countermeasures to deal effectively with the new threat. The Royal Army established on July 1, 1923, within the Engineer Corps, the Military Chemical Service. And within the same, among the specialized battalions established and trained by the Chemical Regiment were the fog battalions. The task of the units belonging to the fog battalions, was to obscure the target from the view of the crews of enemy aircraft, sent to carry out bombing actions, by the formation of an artificial fog.
Fog Units were initially deployed in the immediate vicinity of sensitive targets, later extending their deployment in depth, even kilometers, around the area to be protected, due to the increased intensity and precision of the air offensive. Among the most famous were the reparts sent to the Baltic area at the German allies.