Managing Auditory Risk from Acoustically Impulsive Chemical Demonstrations

• Autores: Jeffrey H. Macedone, Kent L. Gee, Julia A. Vernon
• Localización: Journal of chemical education, ISSN 0021-9584, Vol. 91, Nº 10, 2014, págs. 1661-1666
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Chemical demonstrations are an integral part of the process of how students construct meaning from chemical principles, but may introduce risks to students and presenters. Some demonstrations are known to be extremely loud and present auditory hazards; little has been done to assess the risks to educators and students. Using laboratorygrade equipment, we have measured the average peak sound pressure levels for several common chemical demonstrations, such as methanol cannons, the catalyzed combustion of hydrogen and oxygen, explosive mixtures of gases in balloons, and others. The purpose of this work is not only to determine which reactions pose an auditory risk, but also to investigate alternate presentation methods so that the demonstration can be performed under safe conditions. This included reducing quantities of reactants and the use of a Plexiglas �blast shield� to reduce the intensity of the pressure wave. We also discuss using protective devices to reduce sound pressure levels of the demonstrations.