This question doesn’t come up as often as it should when I do Happiest Baby on the Block consultations. The short answer is that common sense goes a long way to protecting a newborn’s hearing. The longer answer is that understanding sound conduction and newborn development will help parents use white noise confidently. Here we go:
White noise, selected carefully and used with some knowledge, can be a powerful way to calm newborns and it can be a go-to sleep cue for the entire first year. Babies that recognize white noise as a cue that it is time to sleep are easier to calm when the going gets rough. When that first cold, first tooth, or sibling tantrum comes along, the baby who calms automatically with white noise will be easier to soothe. The gift that keeps on giving! Is it addicting? Only as much as your cozy pajamas are on a chilly night! Are Babies Addicted to White Noise? Yes….and No
Sound characteristics for safety and effectiveness are volume and pitch. High pitched sounds are the more dangerous type, especially when used at high volume and close to a sleeping child’s ears. High pitched sounds are also less effective at calming. Examples of high and low pitched sounds? Think about the difference between a whistle (high) and a vacuum (low pitched but loud) or water from a shower head (low pitch and moderately loud). Everyone has heard stories of babies who stopped screaming only if they were next to the clothes dryer or when someone ran the vacuum. Those newborns aren’t excited about housework; the rumbling low frequency sound at a moderate volume helped calm them. Thank goodness that Dr. Karp’s Happiest Baby organization sells while noise CD’s and apps that replicate those calming sounds. I like to vacuum, but not that much!
Babies who scream can easily reach 100 dB (decibel ). That is as loud as a lawnmower! To use white noise to help a screaming baby calm down, you are going to have to turn up the volume temporarily to about 80-90 dB for white noise to have an effect. Remember, I said tem-po-rarily. Once a baby is not screaming, but is still fussy, it is time to lower the volume down gradually to a soft shower level. It is not recommended to use white noise at the volume level above 70dB all night long.
How close should the sound source be to the baby? It depends. Obviously if it too far away, the effect of sound is diminished to the point where it does no good at all. You will realize that quickly as you watch your newborn continue to scream and fuss. Too close is not acceptable either, as the volume of sound will be too high. By the way, Dr. Karp encourages families that want to use a cell phone for white noise to put it on Airplane Mode to diminish the amount of radio waves from the phone. Most phones have tinny speakers that don’t deliver great low pitched sound anyway. The most accurate way to know that the sound is a safe distance is to download a decibel meter app or buy a free-standing meter. Place it next your child and adjust the volume so that the level for an all-night session is 65-70dB. That is about the level of lively conversation, and a safe level for full-term babies.
Should you use white noise all day and all night? Absolutely not. Babies need white noise to sleep and calm, but when awake and interacting, they need to hear your loving voice, experience the quiet stillness of a peaceful home, and listen to the wonderful sounds of nature and family!