A TOPIC THAT COMES UP FREQUENTLY when discussing dive safety is the use of earplugs. Are they safe to use while diving? Can they be used if someone has tubes in their ears due to an ear infection or a ruptured eardrum? Can they prevent swimmer’s ear? Does DAN have any recommendations? These questions are often posted on online message boards and frequently get asked on our medical line.
People might wear earplugs for in-water activities for a multitude of reasons. One underlying premise for using them is to keep the external auditory canal dry, which could help people who have frequent issues such as swimmer’s ear, surfer’s ear or any type of communication through the eardrum (tympanic membrane).
For swimming and other surface activities, earplug use doesn’t have any likely consequences because there isn’t a change in pressure at the surface. For diving, however, earplug use can have detrimental results.
Students in open-water training learn multiple methods to equalize air spaces. Whether it is the Valsalva maneuver or another modified equalization technique, we learn how to push air up through the Eustachian tubes to equalize our middle-ear space. This narrow passage is finicky; if equalization is not done early and often, there can be too much pressure from the underwater environment to effectively move air through them. This is why instructors teach students who are unable to equalize to ascend slightly and try again.
When we equalize successfully, the air that is pushed through the eustachian tubes causes the pressure in the middle-ear space to increase, allowing it to match the ambient pressure from the underwater environment exerted on the outside of the tympanic membrane.
Using traditional earplugs creates an additional air space that your anatomy cannot equalize. The increase in pressure on descent puts pressure on the earplug and pushes it further into the ear due to the decrease in pressure of the air space created. According to Boyle’s Law, the relationship between gas volume and pressure are inversely proportional (of a given mass, at a constant temperature).
If you descend to 3 atmospheres (20m/66ft), for example, air is at one-third of its original volume, including the air in the space the earplug created. To compensate for this, the earplug is forced further into the external ear canal than it should be until it meets too much resistance and stops. At the same time, as long as nothing is blocking the eustachian tube and the diver equalizes or passive equalization occurs, pressure increases in the middle-ear cavity. This increased pressure paired with the decrease in pressure of the air between the eardrum and earplug will cause the tympanic membrane to bow outward. As a diver continues to descend in the water column, the pressure can eventually become so significant that the tympanic membrane can rupture.
One could argue that the use of vented earplugs will mitigate this issue. Vented earplugs allow water to enter the external auditory canal. If the purpose of wearing the earplugs is to keep the external auditory canal dry, however, vented earplugs will not accomplish this because some water will enter the vent and fill the additional space as the air volume decreases.
If divers want to use earplugs for another purpose, such as trying to mitigate issues with caloric vertigo or difficulty with equalization, the vented earplugs can pose the same risks as traditional earplugs if they become occluded. If dirt or debris such as earwax blocks the vent, it has the same result as using an unvented earplug and will likely result in barotrauma.
Some websites sell earplugs marketed toward divers. Some vendors have even claimed that DAN endorses their product. DAN does not endorse the use of any earplugs for diving. Depending on the issue, other options are available.
For issues of communication through the tympanic membrane such as a tympanostomy (tubes) or a perforation, we recommend waiting until they are closed. If they do not close, visit an otolaryngologist to discuss repair options.
To address moisture in the external auditory canal, there are a few different ways to assist your body with draining remaining water from your ears as well as several over-the-counter products that can help restore the ear canal’s natural condition to prevent infections.
Discuss options with your medical provider to determine which is the best choice for you. The DAN medical department is available for consultation should your provider have any questions or concerns. AD
© Penyelam Siaga — Q2 2023