In 1965, the US Chemical Advisor to the South Vietnamese Army’s (ARVN) III Corps participated in planning a “search and destroy” operation in the Iron Triangle, which was known to house an elaborate Viet Cong tunnel system, and suggested using a Mity Mite (Mitey Mite, Mighty Mite) fogger to aid in clearing tunnels (USMACV 1965). On the first day of the operation (October 8th), the force located a tunnel and set into motion an elaborate scheme to fog the tunnels with hexachloroethane (HC) smoke from burning pots, marking the first known tactical use of a thermal fogger to deploy chemical weapons agents (USMACV 1965; Rottman and Delf 2012). Overall, the endeavor was dubbed a success in the report distributed the next month, despite the tunnel having been empty already (USMACV 1965). And although (highly toxic; Simonis (2020)) munitions smoke was used in this application, it was noted that tear gas would be “very effective in flushing VC from tunnels” should there been any present (USMACV 1965).

Technical rendering sketch of a tank with the words Mity Mite on the side. Funnel on bottom of tank leads to exhaust hose below and pipe on bottom of tank has small flexible hose attaching to exhaust hose as well. Exhaust hose comes from below and curves upward to the right. Below the tanks and attached by a frame is a small motor.

Figure 4: Technical drawing of a backpack fogger (USMACV 1965)