University at Buffalo, The State University of New York, USA.
University of Plymouth, UK.
Hum Factors. 2020 Sep;62(6):954-972. doi: 10.1177/0018720819862911. Epub 2019 Aug 14.
This research investigated whether the psychoacoustics of simultaneous masking, which are integral to a model-checking-based method, previously developed for detecting perceivability problems in alarm configurations, could predict when IEC 60601-1-8-compliant medical alarm sounds are audible.
The tonal nature of sounds prescribed by IEC 60601-1-8 makes them potentially susceptible to simultaneous masking: where concurrent sounds render one or more inaudible due to human sensory limitations. No work has experimentally assessed whether the psychoacoustics of simultaneous masking accurately predict IEC 60601-1-8 alarm perceivability.
In two signal detection experiments, 28 nursing students judged whether alarm sounds were present in collections of concurrently sounding standard-compliant tones. The first experiment used alarm sounds with single-frequency (primary harmonic) tones. The second experiment's sounds included the additional, standard-required frequencies (often called subharmonics). tests compared miss, false alarm, sensitivity, and bias measures between masking and nonmasking conditions and between the two experiments.
Miss rates were significantly higher and sensitivity was significantly lower for the masking condition than for the nonmasking one. There were no significant differences between the measures of the two experiments.
These results validate the predictions of the psychoacoustics of simultaneous masking for medical alarms and the masking detection capabilities of our method that relies on them. The results also show that masking of an alarm's primary harmonic is sufficient to make an alarm sound indistinguishable.
Findings have profound implications for medical alarm design, the international standard, and masking detection methods.
本研究旨在调查基于模型检查的方法中同时掩蔽的心理声学是否可以预测符合 IEC60601-1-8 的医疗报警声音是否可听，该方法先前已被开发用于检测报警配置中的可感知性问题。
IEC60601-1-8 规定的声音的音调性质使它们容易受到同时掩蔽的影响：由于人类感官的限制，同时发出的声音会使一个或多个声音不可听。没有工作实验评估同时掩蔽的心理声学是否准确预测 IEC60601-1-8 报警的可感知性。
在两个信号检测实验中，28 名护理学生判断报警声音是否存在于同时发出的标准合规音的集合中。第一个实验使用具有单一频率（主要谐波）的报警声音。第二个实验的声音包括标准要求的附加频率（通常称为次谐波）。t 检验比较了掩蔽和非掩蔽条件以及两个实验之间的错误率、虚报率、敏感性和偏差。
掩蔽条件下的错误率显著高于非掩蔽条件，敏感性显著低于非掩蔽条件。两个实验的测量值之间没有显著差异。
这些结果验证了医疗报警的同时掩蔽心理声学和我们依赖于它们的掩蔽检测方法的预测。结果还表明，报警的主要谐波的掩蔽足以使报警声音无法区分。
研究结果对医疗报警设计、国际标准和掩蔽检测方法具有深远的意义。
