Dolan Thomas G, O'Loughlin Dennis
Department of Speech and Hearing Sciences, Portland State University, Portland, OR 97207, USA.
Am J Audiol. 2005 Jun;14(1):80-5. doi: 10.1044/1059-0889(2005/007).
To determine how amplified earmuffs affect the intelligibility of speech in noise for people with hearing loss, and to determine how various brands of amplified earmuffs compare in terms of speech intelligibility and electroacoustic response.
The Hearing in Noise Test (HINT) was used to measure the intelligibility of speech for 10 participants with hearing loss when they listened in a background of recorded industrial noise at 85 dBA. Participants listened with 3 different sets of amplified earmuffs (Peltor Tactical 7-S, Elvex COM 55, and Bilsom 707 Impact II), with a set of passive earmuffs (E-A-R Ultra 9000), and with ears unoccluded. Two measurements of sentence threshold were obtained under each of the 5 listening conditions. Gain was measured electroacoustically across a range of input levels and frequencies for each amplified earmuff.
Electroacoustic measurements indicated that each electronic earmuff amplified at low input levels and attenuated at high input levels. However, gain characteristics varied greatly across devices. HINT sentence thresholds were not significantly different across the 5 listening conditions or across the 2 trials.
Results suggest that each type of earmuff can be used to reduce the noise exposure of people with hearing loss without compromising their ability to understand speech.
确定放大耳罩对听力损失患者在噪声环境中语音清晰度的影响，并确定不同品牌的放大耳罩在语音清晰度和电声响应方面的比较情况。
使用噪声中的听力测试（HINT）来测量10名听力损失参与者在85分贝A的录制工业噪声背景下聆听时的语音清晰度。参与者分别佩戴3种不同的放大耳罩（3M Peltor Tactical 7-S、Elvex COM 55和Bilsom 707 Impact II）、一组被动耳罩（E-A-R Ultra 9000）以及不戴耳罩聆听。在5种聆听条件下，每种条件均获得两次句子阈值测量值。对每个放大耳罩，在一系列输入电平及频率范围内进行电声增益测量。
电声测量表明，每个电子耳罩在低输入电平时放大，在高输入电平时衰减。然而，不同设备的增益特性差异很大。在5种聆听条件下或两次试验中，HINT句子阈值无显著差异。
结果表明，每种耳罩都可用于减少听力损失患者的噪声暴露，而不会损害他们理解语音的能力。
