Text For Citation: 01 Item/Group: 001A Hazard:

29 CFR 1910.1000(a)(2): Employee(s) were exposed to an airborne concentration of carbon monoxide listed in Table Z-1 in excess of the 8 hour Time Weighted Average concentration of 50 parts per million(ppm) of air: On or about September 12th, 2025, the employer did not ensure that employee(s) were not exposed to an airborne concentration of Carbon Monoxide (CO) in excess of the OSHA's 8 hour Time Weighted Average (TWA) Permissible Exposure Level (PEL) of 50 parts per million (ppm). Employee(s) were exposed to CO produced by a gasoline-fueled Craftsman Pressure Washer while working in the basement of a residential home under construction. Two employees became symptomatic and were transported to a hospital's emergency department for medical care. The CO exposure concentration was derived from employee carboxyhemoglobin levels measured at the hospital. a) An employee using a gasoline powered spray washer was exposed to an 8-hour Carbon Monoxide TWA of 215.4 ppm. This value is 4.31 times the OSHA PEL of 50 ppm and the occupational exposure occurred over 210 minutes. The CO PEL was established to prevent chemical asphyxiation and death. The CO exposure level was derived from employee carboxyhemoglobin blood levels of 33.2%, measured on September 12, 2025. b) An employee using a gasoline powered spray washer was exposed to an 8-hour Carbon Monoxide TWA of 344.0 ppm. This value is 6.88 times the OSHA PEL of 50 ppm and the occupational exposure occurred over 210 minutes. The CO PEL was established to prevent chemical asphyxiation and death. The CO exposure level was derived from employee carboxyhemoglobin blood levels of 30.8%, measured on September 12, 2025. Abatement certification is required for this item in accordance with the requirements of 29 CFR 1903.19(c).