Steve, 
Hope the following is of some help.

>       We are looking into the handling of our humidity sensitive parts.
>We currently keep them in their sealed bags, and reseal unused parts
>immediately after a build(we build very low volumes of boards per day).  

What kind of bags are you using.  If your workplace is higher in humidity,
heat sealing a bag can lock your parts into that environment.  Are you using
dessicant packs in the bags?  How humidity sensitive are these devices and
how do you define such a sensitivity?


> We are considering controlling the environment in the room where we build,
and
>keeping the humidity under 30% to eliminate any moisture build up in the
>parts.  Do I run into other problems, such as ESD issues, and how can I deal
>with those?  

In my opinion, yes this represents and ESD hazard.  Most ESD plans that I
have reviewed have special provisions that must be taken when ambient
humidity falls below 30%, such as ionized air, wrist and foot straps, special
handling, etc.  You might want to check with manufacturing facilities in dry
climates, such as Motorola in Scottsdale, AZ, or NAWC in China Lake, CA
(middle of Mohave Desert).  They routinely deal with low humidity.

>Are there health concerns from running in too dry an environment?  

I would think not, other than drying people out a little.  It has a
preserving effect though.  Some of my former colleages at China Lake are much
older than they look.  You wouldn't know it to look at them, but John Fischer
and Roger Nickell are both over 125 years old.  Unfortunately they can't
leave the desert for more than a week at a time, or they re-hydrate.

Seriously though, unless you install a pure nitrogen system, the health risks
would be minimal.  You might want to check with your local OSHA office on
their guidelines.

Doug Pauls
CSL