All polymer foams are viscoelastic; for foams used in earplugs, this response is essential to their function. Poisson’s ratio was inferred from viscoelastic response of earplug foam in torsion and bending. Poisson’s ratio increases with frequency as a result of stress induced air flow. Air within the pores contributes to the overall bulk modulus at high frequency, but not at low frequency at wh...

Ingestion of a foreign body is common among children. However, ingestion of foam earplugs (FEPs) has not been reported previously. A 7-month-old female infant presented with small bowel obstruction, which was finally proved to be a case of FEP ingestion.Computed tomography (CT) phantom study was performed to examine the imaging features of FEPs. We studied the following dry and fully wet FEPs, ...

INTRODUCTION Intensive care unit (ICU) environmental factors such as noise and light have been cited as important causes of sleep deprivation in critically ill patients. Previous studies indicated that using earplugs and eye masks can improve REM sleep in healthy subjects in simulated ICU environment, and improve sleep quality in ICU patients. This study aimed to determine the effects of using ...

We provide preliminary evidence that listening to music through headphones alters the perception of space around the body -- specifically, the interpersonal distance maintained between the self and others. In comparison to an external auditory environment, wearing headphones or earplugs increased the amount of space maintained between the wearer and another person during an active approach para...

The acoustical attenuation of five different hearing protectors were investigated using real impulses and miniature microphone technique in field conditions from a 23 mm antiaircraft cannon, from 122 mm howitzer and from an explosion of 1 kg of TNT. The measurements were carried out using voluntary military officers exposed to similar impulses in their work. The combination of earmuffs and earp...