预制的耳塞是一种通用的个人防护器材。选用耳塞的办法有:(1)先测外耳道直径,然后选用适当大小的耳塞;(2)不测外耳道大小就给耳塞;(3)由用者自己挑选。作者们试验不同大小的耳塞的效果。大于外耳道直径1mm的实心耳塞可使1000赫以下的噪声平均衰减45.45分贝,使1000至10000赫平均衰减51.3分贝。这比用与外耳道等大或小于外耳道的耳塞,使1000赫以下的音频衰减的效果好得 Prefabricated earbuds are a universal personal protective equipment. The choice of earplugs approach: (1) first measure the diameter of the external auditory canal, and then use the appropriate size of the earplugs; (2) Except for the size of the external ear canal give earplugs; (3) selected by the user himself. The authors tested the effect of earplugs of different sizes. A solid earplug larger than 1 mm diameter of the external auditory canal can attenuate the noise below 1000 Hz by an average of 45.45 dB and attenuate an average of 51.3 dB by 1000 to 10,000 Hz. This is better than using an earbud that is larger or smaller than the external auditory canal to attenuate audio below 1000 Hz