I would urge you to learn more about side effects of using white noise for a baby. These high frequency sounds might cause development problems [1] and also your brain is getting used to them and then it's hard to live in an environment without white noise.
The experiment was _continuous_ white noise, rather than 'while the baby is sleeping' or 'while the baby is falling asleep'.
From the article:
"""Both Chang and Paula Tallal, PhD -- a researcher who was not involved in Chang's study -- say it is probably not a good idea to intentionally expose babies and infants to nonstop white noise, but they say everyday exposures are probably not harmful for most children."""
he says probably, I would not personally risk doing it if I am not 100% sure it's safe. I mean babies don't really need it , why risk it for something that is hardly providing any benefit for a child.
[1] - http://www.webmd.com/baby/news/20030417/white-noise-may-dela...