At 3:35 p.m. on December 27, 2022, an employee was knocking gypsum dust off the interior walls of the end saw baghouse hopper. The baghouse was a large steel structure, 40 feet in height, with inward converging walls that led to two screw-augers that moved gypsum dust to the center of the hopper. The dust would then fall through a central rotary valve and be moved back into the facility. The hopper had vibrators on the exterior siding and pneumatic “poppers” amongst the filter bags to prevent dust build-up. However, when additional moisture was added to the dust, it stuck together. The employer implemented a procedure of deactivating all powered equipment and opening the main hatch to knock the dust down using a stick or a pneumatic air wand. Also, employees could open the two hatches under the auger and use the same method to knock the dust from the bottom of the hopper. Employees were NOT instructed to climb into the hopper.
The employee was providing a tour to a new coworker when the senior supervisor asked him to knock some dust off the inner walls. The employee went to the main hatch and removed the hopper’s dust using a long stick.
