Health hazard evaluation report: HETA-96-0052-2583, National Western Stock Show, Denver, Colorado.
In response to a request from the City and County of Denver's Occupational Health/Indoor Air Specialist, an investigation was begun into working conditions at the National Western Stock Show (SIC-7999), Denver, Colorado. Workers frequently complained of allergic and flu or cold like symptoms such as runny nose, congestion of the nose, throat and lungs, fever, and eye irritation by the end of the show. Measured levels of respirable and total dust, silica (14808607), and carbon-monoxide (630080) were below the recommended criteria levels. Biological activity such as ergosterol, spore count, and endotoxin levels were higher on the first floor of the Hall of Education and in the Stadium Hall, both areas where high numbers of animals were housed. Spore counts and ergosterol levels were consistent with the levels found in other studies where adverse health effects had occurred. Throughout the Hall of Education, the carbon-dioxide (124389) levels were well above the 1,000 parts per million (ppm) level. These levels averaged 2,000ppm and ranged up to 4,300ppm. The need for outside air ventilation throughout the complex was noted. Consistently high readings for carbon-dioxide were also observed in the promenade area around the Coliseum. The authors suggest that the ventilation system in the Event Center be adjusted to introduce outside air for dilution prior to a certain preset time.