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Evaluation of carbon monoxide concentration with and without catalytic emission controls from gasoline propulsion engines.

Garcia A; Marlow D; Earnest GS; Hall RM
Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, EPHB 289-12a, 2007 Apr; :1-33
National Institute for Occupational Safety and Health (NIOSH) researchers evaluated carbon monoxide (CO) emissions and exposures on a ski boat in Punta Gorda, Florida. This evaluation was conducted under an interagency agreement between the U.S. Coast Guard's Office of Boating Safety and NIOSH to evaluate the CO concentrations before and after installing a production catalytic control device to reduce CO concentrations. This catalytic control device was manufactured by Indmar Marine Engines. Similar NIOSH surveys regarding houseboats and other types of recreational boats have been conducted and are described in separate reports. The evaluated boat was propelled by a gasoline-powered engine and could be configured with and without the catalytic converter depending on the evaluation. The boat was evaluated while stationary and at multiple speeds, ranging from 5 to 45 miles per hour (Open throttle). CO concentrations were measured by multiple real-time instruments, which were placed at different locations on the boats. A five gas emissions analyzer was also used to quantify CO emissions from cold crank start at the slip. The Indmar system significantly reduced CO exposures to boat occupants during the current evaluation. For most conditions, a reduction above 90% was observed when compared to a standard exhaust system. This catalytic technology can greatly reduce the CO poisoning hazard to occupants of boats that have gasoline-powered engines. This study specifically evaluated the performance of the Indmar technology designed to reduce CO emissions and protect boat occupants. Engine performance did not seem to be affected by the incorporation of the catalytic converter in the exhaust manifold. The boat with and without the catalytic control device was able to reach the same top speed (45 mph) in about the same amount time. The performance of the Indmar technology was impressive and has the potential of preventing CO poisonings in a variety of settings. Due to the reduction achieved with this technology, the use of these engines with catalyst will reduce CO exposures for people engaging in water sports activities behind the boat as well as boat occupants. The performance of the Indmar system was impressive with CO emissions directly into the exhaust opening of approximately 800 ppm and below for a fully warmed engine. CO concentrations are typically higher at the stern of the boat and become gradually lower toward the front of the boat. In order to ensure that the systems operate effectively, boat owners and operators should ensure that they follow all manufacturers' recommendations with regard to routine maintenance and replacement schedules.
Exhaust-gases; Toxic-gases; Poison-gases; Exhaust-systems; Engineering-controls; Combustion-gases; Combustion-products; Boat-manufacturing-industry; Control-technology; Equipment-design; Region-4
National Institute for Occupational Safety and Health, Division of Applied Research and Technology, Engineering and Physical Hazards Branch, Mail Stop R-5, 4676 Columbia Parkway, Cincinnati, OH 45226-1998
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Field Studies; Control Technology
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NIOSH Division
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National Institute for Occupational Safety and Health
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division