An Analysis of Simultaneous Masking Between Reserved Alarm Sounds of the International Standard
MetadataShow full item record
The international medical alarm standard (IEC 60601-1-8) was created to guide engineers with designing alarms that are easily perceivable by humans. The standard “specifies basic safety and essential performance requirements and tests for alarm systems in medical equipment” (O’Brien 2006). The IEC 60601-1-8 standard contains several reserved alarm sounds that use tonal melodies to represent common types of alarms. Regardless of the standard, practitioners can in any case neglect to hear and react to alarms. This problem has resulted in a significant amount of patient injuries and deaths. Unfortunately, the melodic tonal nature of the IEC 60601-1-8’s alarms makes them susceptible to simultaneous masking, a condition where concurrent sounds interact in ways that make one or more of them imperceptible. It can be difficult to determine how simultaneous masking manifests in medical alarms. This is due to insufficient experimentation in detecting masking in all the potential alarm configurations used in medicine. In this work, we utilize a computational method that employs mathematical proof techniques to determine if masking is possible in a model of a configuration of medical alarms. We use this method to analyze the low and medium priority reserved alarm sounds, of the IEC 60601-1-8 standard at 70 dB and 80 dB. We describe the method, present the results of our analyses, discuss the results, and explore future research directions.