This summary report explains an incident that occurred March 27, 1998, at Union Carbide Corporation's Taft/Star Manufacturing Plant in Hahnville, Louisiana. One Union Carbide worker was killed and an independent contractor was seriously injured due to nitrogen asphyxiation. Safety issues discussed in this report include the hazards of temporary enclosures and the use of nitrogen when working in confined spaces. Recommendations concerning these issues were made to Union Carbide Corporation, the Occupational Safety and Health Administration, and others. This summary report also contains a recommendation to the National Institute for Occupational Safety and Health that it conduct a study concerning the feasibility of odorizing nitrogen when it is used in confined spaces. The Chemical Safety and Hazard Investigation Board (CSB) is an independent federal agency whose mission is to ensure the safety of workers and the public by preventing or minimizing the effects of chemical incidents at industrial facilities. The CSB is a scientific investigatory organization; it is not an enforcement or regulatory body. Established by the Clean Air Act Amendments of 1990, the CSB is responsible for determining the probable causes of incidents, issuing safety recommendations, studying chemical safety issues, and evaluating the effectiveness of other government agencies involved with industrial chemical safety. Section 112(r)(6)(G) of the Clean Air Act prohibits the use of any conclusions, findings, or recommendations of the CSB relating to any chemical incident from being admitted as evidence or used in any lawsuit arising out of any matter mentioned in an investigation report. The CSB makes public its actions and decisions through investigation reports, summary reports, safety studies, safety recommendations, special technical publications, and statistical reviews. A summary report addresses incidents that are within the CSB's jurisdiction, but because of the limited nature of the issues involved, do not require a more comprehensive investigation and report. More information about the CSB may be found on the World Wide Web (http://www.chemsafety.gov).