Image: Dave Buchwald, 2009

We all know that babies can be noisy, but how noisy?

Some screaming babies have been measured at over 110 decibels of sound pressure.

How loud is that?  Very loud!  In an industrial setting this is the one-minute maximum safe exposure level to avoid hearing damage.  Even at 100 decibels for a more moderately screeching  baby the permissible exposure time is just 15 minutes.  This is according to guidelines established by the US National Institute for Occupational Safety and Health (NIOSH) and the Centers for Disease Control.

This supports the adage that parents become deaf to their children’s cries by the time they are two years old.  It may actually be physically true.

Perhaps more importantly, it indicates that there is a danger of physical harm to those nearby, and of extreme nuisance to those further away.  The people that do not want to hear your baby are not necessarily merely being intolerant.

One practical implication of the loudness of baby cries is that the sound is not going to be stopped by just a curtain.