Abstract: At 10:45 a.m. on January 21, 2022, in Building Q, OTC Room, two employees, Employee #1 and Employee #2, were cleaning the top of a mixing tank containing product CS30925, using a broom and dust pan to remove powder/resin accumulation from the top of the tank, when an explosion occurred. Employee #1 and Employee #2 were cleaning resin powder from the top of the mixing tank, containing a highly flammable liquid (possibly acetone-product CS30925), using a broom and dust pan. However, a shop vacuum was found on the catwalk, by the Hazardous Materials Team, and it was believed that it caused an energized electrical event, igniting the dust and causing an explosion and fire. It is unsure in which location each employee was working at, when the explosion occurred. Employee #1 was found in a harness and dead upon emergency services arrival. Employee #2 was on the ground walking disoriented when emergency services arrived, and life-saving efforts were conducted. Employee #2 was taken for treatment of chemical and flash burns to Saint Anthony's in Rockford, Illinois. Employee #2 was in stable but critical condition.