We find white nose to be extremely effective for soothing our 5-week old son. Loud white noise (60 decibels or so) will help soothe him when he is overtired and crying, and if we play soft white noise (40-50 db) near him as he sleeps he is much less likely to fully wake himself up when he stirs.
But I have a few concerns:
Will hours of white noise a day cause hearing damage? We make sure that sustained volumes are always less than 60db which is below any level for hearing damage, but the temptation is to have it going whenever he is asleep and I can't find any data if long term, low volume of a constant sound can be detrimental to an infant's hearing.
Will this become a crutch he will need to get to sleep even when he's much older? On one level that wouldn't be so bad since it is extremely easy to provide (just flip on an iPhone app). But I'd hate to make things more difficult for us down the line.
Anyone with experience or knowledge on this? The only study I could find exposed rats to 24/7 noise and predictably it delays their ability to recognize other sounds. But we obviously don't use it even close to constantly.