Development of field methods for assessing auditory situational awareness when using hearing protective equipment in the noisy workplace

在许多职业环境中，工人暴露于可能对听力健康和工作安全产生不利影响的机器和设备的高水平噪音中。虽然从源头上对噪声进行工程控制是首选的解决方案，但以这种方式将噪声降低到安全水平并不总是可行的，因此经常需要使用个人听力保护器（如耳罩和耳塞）。目前关于听力保护器的选择、安装和使用的标准侧重于确定这些设备必须提供的噪声衰减的方法，以满足最大每日声音暴露的法规限制。然而，在焦点小组会议上，工人们经常担心在使用听力保护器时缺乏听觉情境意识，因为这些设备会降低他们对周围环境中重要声音的反应能力，并干扰口头交流。目前的标准只提供了关于通信要求的一般指导，而不是针对个别工人的需求、听力状况、工作要求或工作场所噪音的具体要求。本研究计划的目标是开发听觉测试，可以被职业利益相关者用来衡量听力保护器对他们自己工作场所情境意识的影响。两个主要目标是：(1)开发工具来评估特定工人在工作场所噪音中佩戴他/她指定的听力保护器时的语音感知，以及(2)开发测试模块来评估关键工作场所声音的可听性和识别性（例如，警报，接近车辆的声音，机器故障的声音提示），这些声音对于确保佩戴听力保护器时工作场所的安全和高效操作至关重要。这些测试的主要设计要求是它们可以在工作场所环境中快速（例如，<10分钟）进行，并具有良好的心理测量特性（例如，测试重测信度）。计划对人类参与者进行实验，以评估拟议的测试。验证将在年龄、性别、语言能力和听力状况方面对广泛的成人测试参与者进行。综上所述，本研究项目将有助于我们对噪声、听力保护和听力状况之间复杂的相互作用的基本理解，并有助于开发实用工具，以帮助选择既考虑保护需求又考虑交流需求的听力保护器。反过来，这将支持制定或修订最佳选择听力保护器的国家和国际职业标准程序。

In many occupational settings, workers are exposed to high levels of noise from machinery and equipment that can adversely impact on hearing health and job safety. While engineering control of noise at the source is the preferred solution, it is not always feasible to reduce noise to safe levels in this way and the use of personal hearing protectors (such as earmuffs and earplugs) often becomes necessary. Current standards on the selection, fit and use of hearing protectors focus on methods to determine the noise attenuation that these devices must provide to satisfy regulatory limits on the maximum daily sound exposure. In focus group meetings, however, concerns are often raised by workers about the lack of auditory situational awareness when working with hearing protectors as these devices can reduce their ability to respond to important sounds from the surrounding environment and interfere with verbal communication. Current standards only provide general guidance regarding communication requirements that is not specific to the individual worker's needs, hearing profile, job requirements or workplace noise. The goal of this research program is to develop auditory tests that can be used by occupational stakeholders to measure the effects of hearing protectors on situational awareness in their own workplaces. The two main objectives are to (1) develop tools to assess speech perception when a given worker wears his/her assigned hearing protector in workplace noise, and to (2) develop a test module to assess the audibility and recognition of critical workplace sounds (e.g., alarms, approaching vehicle sound, acoustic cue from machine malfunction) that are important to ensure safety and efficient operations in the workplace while wearing hearing protectors. Key design requirements for these tests are they could be administered quickly (e.g., <10 min.) in workplace environments and possess good psychometric properties (e.g., test-retest reliability). Experiments with human participants are planned to evaluate the proposed tests. Validation will be conducted over a wide range of adult test participants in terms of age, gender, language proficiency and hearing profile. Overall, this research program will contribute to our basic understanding of the complex interaction between noise, hearing protection and hearing status on auditory perception as well as to the development of practical tools to assist in the selection of hearing protectors that considers both protection and communication needs. This, in turn, will support the development or revision of national and international occupational standard procedures for the optimal selection of hearing protectors.