UNITED STATES
DEPARTMENT OF LABOR

At 07:30 a.m. on August 17, 2018, Employee #1, a Supervisor, was cutting a concr ete floor (indoors) using a gas-powered saw, during a plumbing construction proj ect. Other coworkers, including: Employee #2 performed work adjacent to this operation. The Employer outfitted the concrete saw with an oxidation catalyst, exhaust scrubber, which is required to reduce dangerous concentrations of harmfu l Carbon Monoxide (CO) and particulate matter; however, no atmospheric monitorin g was performed during the first hour of the operation to evaluate exposure lev els. The employer mandated use of N95 filtering facepiece respirators to reduc e exposure to silica; however, workers were untrained, as to the limitations of the N95 respirator, e.g., does not offer protection against chemicals, gases, or vapors, such as: "sewer smells", etc., in the work environment. The employer installed two large circular fans, as a means for exhaust; however, an effectiv e ventilation system was not used to eliminate Carbon Monoxide from the work are a. In consequence, Employee #1 was hospitalized after being overexposed to CO a nd Employee #2, Plumber/Coworker, exposed during work task performed adjacent to CO emissions, sustained low-level exposure to CO and suffered bodily symptoms, such as: dizziness, drowsiness, and weakness.