computer building? was[rescue] Noise levels

[James Lockwood]

On Wed, 19 Jun 2002, Gary Nichols wrote:

> I cannot (repeat) CANNOT work for more than an hour under flourescent
> lighting.  I get bad headaches because I'm one of those freaks of nature
> that can actually see the shimmering.  Sitting in my office at work is
> like a bad acid trip sometimes.  I've been this way all my life.  I
> thought other people could see them too and just thought "well, I guess
> they are supposed to work that way".  Needless to say I leave my office
> for about 10 mins every hour just to rest my eyes.

You are probably seeing 120Hz flicker from magnetic or older electronic
ballasts.  This can be within the human range of perception, especially if
the bulbs are at all worn, cold, or of the "energy saving" variety.  I see
flicker in my T12's in my garage, but I supplement them with other
lighting.

I recommend both you and Tim check out some good modern fluorescent (this
does not mean T12!) fixtures with new electronic ballasts.  These now run
in the 20KHz range and any flicker is totally beyond the perception of the
human eye.  Many buildings are not replacing old fixtures or are
"replacing as they go", and the cheapest fluoro fixtures are still running
at 120Hz.  The nice ones don't address the color purity issue (which is my
biggest problem) but they do solve flicker.

-James