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NORA Manufacturing Sector Strategic Goals

927001Z - Control of Carbon Monoxide on Houseboats and Marine Vessels

Start Date: 1/1/2001
End Date: 9/30/2011

Principal Investigator (PI)
Name: Alberto Garcia
Phone: 513-841-4596
Organization: NIOSH
Sub-Unit: DART
Funded By: NIOSH

Primary Goal Addressed

Secondary Goal Addressed


Attributed to Manufacturing


Project Description

Short Summary

Control of Carbon Monoxide on Houseboats and Marine Vessels in an on-going project whose main purpose is to evaluate and recommend effective engineering controls to reduce carbon monoxide poisonings on houseboats and other marine vessels. Numerous field evaluations have occurred for controls that document major reductions in CO and will ultimately prevent CO poisonings.

This project addresses the many of the Cross Sector Program Engineering Controls:

1. Reduce occupational illness through research on and the advancement of new or retrofit engineering control technology.
2. Develop and build recognition and awareness of occupational safety and health hazards and the means for controlling them by creating control technology information that promotes technology transfer, as well as, the education and training of management, workers, health and safety professionals, and the media

The knowledge gained by the research conducted on this project enabled NIOSH researchers to be involved on an Underwriters Laboratories (UL) consensus standard that addresses issues with portable generator assemblies. This involvement is also considered influential to the PtD Cross Sector as it investigates the motivators, enablers, and barriers to PtD implementation.

Outcomes include technical reports, journal articles, and professional presentations that have already influenced the marine industry. The products of this project are used in the marine industry to reference and propose new construction and technologies to provide a safer marine environment. This work has also influenced EPA regulations for the marine industry where cleaner burning/low CO emission generators and engines are required in all new boats.


The goal of this project is to assist manufacturers and governmental agencies in evaluating and recommending controls to reduce carbon monoxide poisonings on recreational boats.

Work on this project has shown that there is a significant CO problem on many types of recreational boats including ski boats, cabin cruisers, express cruisers, and houseboats. Methods used to conduct this research included air sampling with a variety of technologies and computer modeling with FLUENT software to assist in evaluating more complex issues. Computational fluid dynamic (CFD) modeling was used to evaluate the effect of worst case ambient conditions, including temperature and wind velocity, on carbon monoxide dispersion characteristics. CFD was used to solve the fundamental equations of fluid flow and heat transfer, providing a detailed description of the flow field. CFD has provided spatially and temporally resolved values of temperature, air velocity, and contaminant concentrations that were used in evaluating engine exhaust designs under various conditions. Results of the CFD modeling were shared with both the U.S. Coast Guard and the EPA.

A national workshop was organized by NIOSH and the Coast Guard in late March 2003 in Annapolis, Maryland to discuss engineering solutions for controlling CO on recreational boats. The workshop was well attended and continued the momentum toward eliminating this hazard. Throughout the project, results have been disseminated through technical reports, journal articles and conference presentations. This work has influenced EPA regulations for the marine industry where cleaner burning/low CO emission generators and engines are required in all new boats.

NIOSH researchers conducted numerous evaluations on express cruisers using gasoline propulsion and power generation engines. Information was compiled and analyzed with signs of dramatic exposures while underway at speeds lower than 15 mph.

Canvas configuration is another CO-related issue on express cruisers where it is commonly misused by owners and users.

Educational documents were created that illustrate the adverse effects of deploying the canvas for a function other than that for which it was intended.

This project has addressed many critical components that contribute to potential overexposure to CO on marine vessels. The research knowledge generated by this project, with input from the marine industry, other government agencies, policymakers, and research leaders changed the concept of marine industry and introduced safer technologies, rules and regulations, and educational documents that will ultimately reduce the risk of CO overexposure to occupants in and around marine vessels.

Mission Relevance

More than 800 boating-related carbon monoxide (CO) poisonings have been identified on U.S. waters. Approximately 50% of the poisonings occurred on houseboats and the remainder on other types of boats. One-hundred twelve of the poisonings occurred outdoors; 32 of these people died. CO exposures exceeding the NIOSH IDLH level of 1,200 ppm is not uncommon on many types of recreational boats because most of them use uncontrolled gasoline-powered engines.

The aims of this project are also to reduce hazardous occupational exposures through the advancement of control technology and address the following goals. 10PPENGSG1 Reduce occupational illness through research on and the advancement of new or retrofit engineering control technology; 10PPENGAOG1.1.3 Control of carbon monoxide (CO) on houseboats and marine vessels; 09PPENGSG3 Reduce occupational illness and injuries by providing expert advice and consultation to our partners on engineering controls; 10PPENGAOG3.2.2 Promote the use of engineering controls to control carbon monoxide emissions to regulatory agencies and consensus standard bodies. 09PPENGSG4 Develop and build recognition and awareness of OSH hazards and the means for control through technology transfer, education, and training. 10PPENGAOG4.4.1 Promote the use of technologies to control carbon monoxide on marine vessels; 10PPENGIG5.2 Incorporate engineering control solutions into standards and regulations; 10PPENGAOG5.2.2 Disseminate engineering control research findings in the marine industry to appropriate agencies and trade associations.

The National Institute for Occupational Safety and Health (NIOSH), the Department of the Interior (DOI), the National Park Service (NPS), the U.S. Coast Guard (USCG), and many partners investigated carbon monoxide (CO) deaths, evaluated other CO-related boating incidents, and developed engineering controls to prevent future poisonings. The investigative team discovered over 800 boat-related CO poisonings on U.S. waters since 1990 that were caused by gasoline-powered propulsion engines and onboard generators that provide electrical power. The team worked closely with many boat and marine engine manufacturers and trade associations to define the extent of the hazard, determine employee exposures, develop engineering controls to mitigate the CO hazard, and educate the public.

The Double Angel Foundation is a non-governmental organization that keeps track of CO related poisonings and produces a National Case Listing that includes lethal and non-lethal poisonings.

For the last several years, NIOSH researchers have worked with trade associations, regulatory agencies, boat manufacturers, and other companies to evaluate the effectiveness of CO control devices. We have identified several controls that could dramatically reduce the number of CO poisonings on recreational boats: 1) a stack that reroutes generator emissions; and 2) electronic fuel injection and catalysts on engines that eliminate CO before it exits the exhaust.

The USCG funded much of this work through an interagency agreement. Due to the magnitude of the problem, Congressional hearings have been held on this topic. Research results are regularly shared with the Coast Guard, Environmental Protection Agency, the American Boat and Yacht Council (ABYC), and the National Marine Manufacturers Association.

Future cooperative work will involve the continued evaluation and identification of factors leading to CO poisonings on Express Cruisers, evaluating the performance of a new Kohler low emission generator, evaluating the performance of Indmar Marine Engine catalysts for inboard engines, and the evaluation of control systems for towed sports activities.