Today we were under a heat and air pollution alert in the St.
Louis Metropolitan area. The hottest temperatures on record
since 1991, and several area ozone monitors exceeded the EPA
maximum standards. This brought me to thinking about the hours
and hours I have spent in closed garages sweating it out with 
killowats of restive ballast and ozone so thick it litterally
choked those who were not acclimated to the foul air.

I am a firm believer that a little ozone is stimulating, and that
this highly reactive gas oxidizes many common air pollutants, but
is that all a coiler is exposed to? Is it really safe to breath
the exhaust gasses from the main system spark gap for long
periods of time in a closed enviroment?


Chemical reactions take place where corona and discharges from
the secondary coil ionize the air. Chemical reactions also take
placed in the arc of the main system spark gap. Most of the
ionization and secondary discharges produce ozone, but the arc at
the main system spark gap is so hot that various nitrogen oxides
are also produced. Rather than try to research all of the
possible physiological effects of these gasses indivually or in
combination, their toxicity levels, etc., I will try to give some
simple guidelines towards common sense prevention, and list some
common symptoms of overexposure.

The first thing that the coiler needs to be aware of is that the
sense of smell becomes accustomed to the presence of these gasses
and that the nose is not an accurate means of determining
exposure levels. I have on many occasions spent hours cooped up
with a coil, performing experiments fairly comfortably, when
someone else walked in from outside and complained bitterly about
the ozone and nitrogen oxide levels being quite toxic. Since the
complainer was a licensed physician who has researched the
medical effects of ozone in high concentrations, I was forced on
more than one occasion to heed the advice to shut down and
ventilate before I resumed spinning the wattmeter. 

First some guidelines:

1) You smell ozone, but it is not strong. You have not been
firing for more than 15 minutes cumulative. Your ventilation is
good (complete air exchange every 15 min). Everything is fine.

2) You don't smell strong ozone, but you have been firing for
more than 15 minutes cumulative without good ventilation. In this
instance your nose is accustomed and is no longer an accurate
gauge to your exposure to these toxic gasses. You may be
overexposed, then again you may not.

3) Your eyes water and burn. Your throat burns. You feel a slight
respiratory congestion. If you experience any one, or a
combination, of these symptoms: shut down and ventilate. Do not
resume without a complete air exchange. Leave the area while

I was warned by the physician mentioned above that long term
exposure to high levels of ozone will damage the corneas of the
eyes, but I have never encountered or heard of a case where
anyone has suffered ocular damage as a result of exposure to
ozone levels typical to coiling. However I have discovered that
in over 50% of those coilers whom I questioned, overexposure to
coiling gasses trigger intense migraine headaches. These
headaches typically do not start until the day following the
overexposure. They tend to be quite intense, cannot be treated
effectively with over the counter pain relievers, and usually
last from four to eight hours.

I have had perhaps two migraine headaches in my entire life
before I started coiling. Even with the coiling I was fine until
I was consistantly firing at power levels over 1.5 kVA. Soon
however, I found myself having three or four genuine migraine
headaches a week. The headaches started mid-morning and lasted
all afternoon. I was finally able to determine that my migraines
were directly related to my exposure of ozone and nitrogen oxides
as a result of high powered coiling in a poorly ventilated area.
Before I was able to make this connection (about two weeks) I was
spending a good deal of time painfully ill and I missed a
respectable amout of work as a result. 

During one of my annual jaunts somewhere to meet up with other
coilers, I related my experiences to a group and was surprised at
the number of others who had had similar battles with migraines.
About half of those whom had been affected had already made the
connection to their exposure to coiling gasses, the others were

Later, in an effort to increase my power levels while reducing my
discomfort, I discovered that simply venting out the gasses from
the main system spark gaps was very helpful. Apparently, and this
is a supposition, the combination of ozone with nitrogen oxides
is more detrimental than exposure to ozone alone.

By fitting my cylinder static gaps with plastic dryer ducts and
venting the ducts outside I was really able to reduce both the
room ventilation requirements, and the headaches. With a little
bit of awareness and practice I am now able to determine when I
am reaching toxic blood levels before I am overexposed to the
point that I am subject to getting a migraine the following day.

Just thought I might pass these little pointers along.

Richard Quick

... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12