My wife Karen Bahr pointed out your concern to me. There seems to be
a lot of response to your query by people that are mostly correct but
conclusive knowledge is helpful when overcoming fear of any kind.
The voltage (Volts) is the force which drives the current (Amps)
through any circuit and the resistance of the circuit (Ohms) is what
opposes that current flow. If you don't li+ke abstract thinking,
consider this system as equivalent to a water pump which pushes the
water flow through a restrictive size of pipe.
Only salt water is a conductor while plain water is only a
semiconductor with a much higher resistance. This is good to know
when trying to get an electric lawn mower with a wiring problem to
start, with sweaty hands. For lower voltages, like your 12 volt
application, a little resistance such as normal, dry skin resistance
is quite sufficient to oppose the flow or current to very safe levels
while you do your electrical plating or other processes.
Current pathway is absolutely necessary for electrocution to occur
regardless of voltage or the current it causes. This means the
current has to go through your heart during this situation, even on
line voltages to your home at the electrical panel. Your feet have to
be grounded very well through sweaty socks and poor shoes on a
somewhat conductive floor like damp concrete or your other hand has
to come into contact with the grounded panel housing or any water
pipe nearby which is also a ground connection. This situation has to
be in place while you deliberately touch a live 120 volt connection
in your electrical panel.
Lethal electrical shocks also have to happen when a person's heart
is in the correct phase. If the shock occurs just when the heart is
changing state from closed to open or open to closed and if the
current is at 35 ma. or more (Thousandths of one amp.), then the
heart will likely go into fibrillation and a hospital with a
defibrillator is the only way or correcting this if time permits.
A person's body is a bioelectrical unit which uses electrical pulses
from the brain to control muscles. When a person feels a slight
tingle from a shock, they are already around the 20 ma. range of
current flow. At 25 ma. the current is already high enough to start
overriding the control from the brain and causes the hand or other
muscles to clench tighter and letting go becomes less of an option.
The tighter grip lowers skin resistance and higher current occurs as
the danger increases.
Naturally, you sound like a person who is unlikely to be messing in
their electrical panel anyway but the info is good to know and may
allay some of your concerns about lower power capacities in various
Your variable current output up to 5 amps on your machine infers to
me your liquid process solution has to be quite conductive or that
low voltage would not be able to push anything near 5 amps through
that liquid. A comparison of safe voltages using a 9 volt battery is
not valid to me since that battery is current limited and likely
cannot deliver anything lethal under any conditions.
Because your process liquid sounds quite conductive, please use
rubber gloves during this part of your work and dry shoes if on
concrete floors. If the rubber gloves become wet inside with solution
and the current path is not good, I believe there is some risk and
suggest you change to dry gloves immediately.
As far as gas risk from the process, I agree that could be
substantial. Consider the path of the gas during this work and locate
your exhaust fan is the appropriate location to prevent breathing
anything harmful. I mounted Karen's exhaust fan right in her bench as
apposed to any ceiling unit. This way any fumes or gases are
exhausted before they reach nose level.
I hope this info gives you a more comprehensive understanding of
electrical hazards and how to feel more comfortable around any kind
Dan Bahr, Master Electrician Certification
Husband of Karen Bahr