The question of whether white noise can cause or cure the ringing sensation known as tinnitus is a common concern for people using sound machines for sleep or focus. White noise is a unique acoustic signal defined by having equal energy across all audible frequencies, resulting in a static-like, steady hissing sound. Tinnitus is the perception of sound when no external source is present, often described as ringing, buzzing, or hissing. This article explores the scientific distinction between the sound’s structure and its volume to address the fear that this popular sound can damage hearing.
The Science of Sound and Tinnitus Causation
Tinnitus is generally a symptom of an underlying issue, most commonly damage to the auditory system. The primary cause of permanent tinnitus is Noise-Induced Hearing Loss (NIHL), which results from the destruction of the delicate hair cells (stereocilia) within the cochlea of the inner ear. These cells translate sound vibrations into electrical signals the brain interprets. When they are damaged, the brain may compensate by generating the phantom sound of tinnitus.
The risk to hearing health does not come from the specific frequency profile of the sound, such as the flat spectrum of white noise, but rather from the sound’s intensity, or volume. White noise, when played at a moderate level, is acoustically benign and does not inherently damage the cochlea. The danger lies entirely in the decibel level and the duration of exposure. Therefore, white noise itself does not cause tinnitus; excessive volume is the true risk factor for hearing damage.
Defining Safe Listening Levels for White Noise
To prevent hearing damage, listeners must adhere to safe listening thresholds, regardless of the type of sound used. For continuous exposure, sounds at or below 70 decibels (dB) are considered safe for adults for any length of time. Exposure to noise at 85 dB and above, such as heavy city traffic, can lead to permanent hearing loss over an extended period.
The safe exposure time decreases rapidly as the volume increases. For example, listening at 85 dB for more than eight hours a day can cause damage, and this safe duration is cut in half for every 3 dB increase above that level. For adults using a white noise machine for sleep, the recommended volume range is between 50 and 70 dB, which is loud enough to mask distracting sounds without posing a risk.
White Noise as a Tinnitus Management Tool
White noise is a standard and effective tool frequently used by clinicians to manage existing tinnitus symptoms. The sound is often incorporated into structured treatment plans like Tinnitus Retraining Therapy (TRT). The therapeutic benefit is achieved through two main mechanisms: masking and habituation.
Masking involves introducing a low-level external sound to reduce the contrast between the perceived tinnitus sound and the quiet environment. The white noise offers a consistent background that makes the tinnitus less noticeable without completely drowning out the ringing. Habituation is a long-term goal that trains the brain to reclassify the tinnitus signal as unimportant, much like tuning out distant traffic.
By providing constant, neutral auditory input, white noise helps the brain shift focus away from the internal sound. This sound enrichment is particularly helpful in quiet environments, such as when trying to fall asleep, where tinnitus is often most intrusive. The goal is to integrate the white noise at a volume slightly below the loudness of the tinnitus, encouraging the brain to adapt to the combined signal.
Safe Application and Alternative Sound Therapies
Using sound machines safely involves more than just volume control, particularly for continuous use. A key safety guideline is to place the sound machine at a distance, ideally at least seven feet away from the head or a baby’s crib. This distance helps ensure the sound level measured at the ear remains low. The American Academy of Pediatrics recommends that sound in a baby’s sleep environment should not exceed 50 dB.
For adults, it is best to use the sound only as needed, rather than running it all night. Users should also avoid using earbuds or headphones for continuous white noise, as these devices deliver sound directly into the ear canal and make it more difficult to gauge safe volume.
For those who find the high-frequency content of true white noise too harsh, alternative “colored” noises are available. Pink noise, which has less energy in the higher frequencies, is often described as sounding like a waterfall or steady rain and may be perceived as softer. Brown noise, with even lower frequencies, offers a deeper, more resonant sound, like the roar of a river, and is a popular alternative.