Alberti P W, Riko K, Abel S M, Kristensen R
J Otolaryngol. 1979 Aug;8(4):354-9.
A series of workmen being evaluated for pensions for occupational hearing loss were asked to bring their own hearing protectors from work, to fit them themselves, following which attenuation studies were made. The muffs and most earplugs produced similar attenuation levels at high frequencies, although the muffs produced less attenuation at low frequencies. In all cases the mean attenuation was significantly lower than optimum figures suggested in the literature, and the standard deviation was relatively high. Personally molded earplugs were significantly less effective than other plugs used. Reasons are discussed for the relatively poor performance of these devices and the concept of assumed protection, i.e. mean minus one standard deviation, is discussed. There is need for better instruction on how to use hearing protectors if they are to be effective.
一系列因职业性听力损失而接受养老金评估的工人被要求从工作场所带来自己的听力保护器，并自行佩戴，随后进行了衰减研究。耳罩和大多数耳塞在高频时产生的衰减水平相似，尽管耳罩在低频时产生的衰减较小。在所有情况下，平均衰减均显著低于文献中建议的最佳数值，且标准差相对较高。个人定制的耳塞比其他使用的耳塞效果明显更差。文中讨论了这些装置性能相对较差的原因，并探讨了假定保护的概念，即均值减去一个标准差。如果要使听力保护器有效，就需要更好地指导如何使用它们。
