NIOSHTIC-2 Publications Search
A hot topic: improving ventilation equations for exothermic processes.
McKernan J; Ellenbecker M
American Industrial Hygiene Conference and Exposition, May 21-26, 2005, Anaheim, California. Fairfax, VA: American Industrial Hygiene Association, 2005 May; :65
Exothermic processes create potentially unsafe work environments for an estimated 5-10 million American workers. These processes are present in a multitude of industries including chemical, plastic, rubber, glass, and primary metals. Although excessive heat and process contaminant exposure have the potential to cause adverse health effects in workers, insufficient attention has been given to improving engineering control technologies for these processes. The objective of this research was to investigate this knowledge gap. A review of historic and modern heat transfer and meteorological theory were conducted, leading to the development of new ventilation equations to provide improved control of exothermic processes. Subsequently, laboratory data were collected to validate the new and currently accepted ACGIH equations. In laboratory experiments, axisymmetric centerline velocity data were collected using a hot-wire anemometer at varying heights above a model exothermic process. Laboratory results were compared to predicted results from both the new and ACGIH equations. Statistical analyses were conducted for the difference between the laboratory velocity results and predicted velocity results from both the ACGIH and new equations using a one-sample t-test. Mean difference, variance of the difference and t-test p-values when comparing the ACGIH equations with laboratory data were 0.016 m/s, 0.005, <0.0001. Mean difference, variance of the difference and t-test p-values when comparing the new equations with laboratory data were -0.006 m/s, 0.006, 0.298. Analyses indicate that the new equations have the potential to more accurately predict ventilation rates to capture the entire potential thermal plume flow.
Ventilation-systems; Ventilation; Work-environment; Workers; Engineering-controls; Safety-research; Laboratory-testing; Models; Statistical-analysis; Chemical-reactions; Plastics-industry; Rubber-manufacturing-industry; Glass-manufacturing-industry
American Industrial Hygiene Conference and Exposition, May 21-26, 2005, Anaheim, California
Page last reviewed: March 11, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division