Re: how is static electricity produced in connection to low humidity?

As you already know, static electricity is produced by charges 
accumulating on a body or object and is usually induced by friction:  the 
electrons literally "rub off" from one object to another.  This includes 
the friction generated by walking with shoes across a carpet.  OK, but 
this does not answer your question.  The answer is surprisingly simple:  
air can be quite conductive or only very slightly conductive depending on 
the humidity due to a phenomenon called "hydrogen bonding":  the hydrogens 
on one water molecule are attracted to the oxygen atom on the next 
molecule over.  If there is high humidity, there is a great deal of 
hydrogen bonding and the air's electrical resistance is low, allowing 
static charges to "bleed off" to an oppositely charged body.  When the air 
is dry, the air is not conductive due to a lack of water vapor and so 
static charges stay where they accumulate and you get a shock every time 
you touch something.  The problem is especially critical in electronics 
work, where a small static discharge, usually too small to feel, can 
destroy an expensive integrated circuit.  So humidity in these areas is 
strictly controlled to around 50% to ensure conductive air and minimize 
static charges.