Start with less exposure
The American Academy of Pediatrics advises putting an infant sleep machine as far from the baby’s head as possible and using it only for a short time. Its broader noise guidance also recommends reducing device volume and making room for quiet.
Keep the phone, speaker and cables outside the sleep space. Sound does not make a sleep setup safe: follow the AAP guidance on a firm, flat surface, placing a baby on their back and keeping the sleep space clear.
Source: AAP: How noise affects children · AAP: Safe infant sleep setup
Why a browser cannot certify the level
The loudness reaching a baby depends on the sound file, software gain, device volume, speaker, room and distance. The percentage on this player is a software control. It is not dBA and cannot measure exposure at the child’s ear.
Our default volume and timer are interface starting points, not pediatric limits. A gentle name, a darker noise color or a digitally attenuated file is not evidence that every playback setup is safe.
What machine-output research tells us
A 2014 study measured 14 infant sleep machines at maximum volume at several distances. All exceeded 50 dBA at 30 cm. The study used a hospital-nursery reference for that number; it did not establish a universal home-playback threshold.
That experiment tested machines, not this browser’s files. It shows why device output and position deserve attention. It does not let this site label a percentage, distance or all-night duration as universally safe.
Source: Hugh et al., 2014: output levels of infant sleep machines
Benefits and uncertainties
Sleep and hearing responses vary. This tool does not establish that background noise is necessary, safer than silence or a treatment for a sleep problem. Adult noise experiments cannot be directly applied to babies.
If you have concerns about hearing, persistent crying or sleep, consult your child’s clinician. Stop sound if it seems unwelcome. Do not use the player as a substitute for checking on a child.
Sources and limits
These sources support the factual explanations. They do not endorse this site or certify a particular playback setup.
- AAP: How noise affects children
- AAP: Safe infant sleep setup
- Hugh et al., 2014: output levels of infant sleep machines
Sources checked October 10, 2026. Written for this project; no clinical review is claimed.