Editing Earplug (section)

===Protection from water===
Some earplugs are primarily designed to keep water out of the ear canal, especially during swimming and water sports. This type of earplug may be made of wax or moldable silicone which is custom-fitted to the ear canal by the wearer.

Exostosis, or [[surfer's ear]], is a condition which affects people who spend large amounts of time in water in cold climates. In addition, wind may increase the prevalence of the amount of exostosis seen in one ear versus the other dependent on the direction it originates from and the orientation of the individual to the wind.<ref name="King">{{cite journal|last=King|first=John F.|year=2010|title=Laterality of Exostosis in Surfers Due to Evaporative Cooling Effect|journal=Otology & Neurotology|volume=31|issue=2|pages=345–351|doi=10.1097/MAO.0b013e3181be6b2d|pmid=19806064|s2cid=205754007|display-authors=etal}}</ref> Custom-fitted surfer's earplugs help reduce the amount of cold water and wind that is allowed to enter the external ear canal and, thus, help slow the progression of exostosis.

Another condition is [[otitis externa]], which is an infection of the outer ear canal. This form of infection differs from those commonly occurring in children behind the eardrum, which is otitis media, or a middle ear infection. This infection's symptoms include: itchiness, redness, swelling, pain upon tugging of the pinna, or drainage. To protect from this form of infection, it is important to thoroughly dry the ears after exposing them to water with a towel. To protect the ears during exposure, the individual can use a head cap, ear plugs, or custom-fitted swim molds.<ref>{{Cite web|url=https://www.cdc.gov/healthywater/swimming/swimmers/rwi/ear-infections.html|title=Ear Infections {{!}} Healthy Swimming {{!}} Healthy Water {{!}} CDC|date=2017-06-19|website=www.cdc.gov|language=en-us|access-date=2018-03-09}}</ref>

A 2003 study published in ''Clinical Otolaryngology'' found that a cotton ball saturated with petroleum jelly was more effective at keeping water out of the ear, was easier to use, and was more comfortable than wax plugs, foam plugs, EarGuard, or Aquafit.<ref>{{cite journal |doi=10.1111/j.1365-2273.2004.00795.x |title=An objective evaluation of the waterproofing qualities, ease of insertion and comfort of commonly available earplugs |year=2004 |last1=Chisholm |first1=E.J. |last2=Kuchai |first2=R. |last3=McPartlin |first3=D. |journal=Clinical Otolaryngology and Allied Sciences |volume=29 |issue=2 |pages=128–32 |pmid=15113295}}</ref>

[[Jacques-Yves Cousteau]]<ref>''[[The Silent World: A Story of Undersea Discovery and Adventure|The Silent World]]'' (New York:1953, Harper, pp. 5-6)</ref> warned that earplugs are harmful to divers, especially [[Scuba diving|scuba divers]]. Scuba divers breathe compressed [[air]] or other gas mixtures at a pressure matching the water pressure. This pressure is also inside the ear, but not between the eardrum and the earplug, so the pressure behind the eardrum will often burst the eardrum. Skin divers have less pressure inside the ears, but they also have only atmospheric pressure in the outer ear canal. The PADI (Professional Association of Diving Instructors) advises in the "Open Water Diver Manual" that only vented earplugs designed for diving should be used in diving.