People who see the "surfing"
picture tend to be somewhat concerned with my safety, given the
truism that water and electricity are not supposed to mix. In fact,
my surfing setup is as safe as I can make it.
- The shelf supporting the laptop is very stable, being rigidly
fastened to the bathtub on both sides.
- The laptop runs on 12 volt DC, not 120 volt AC. If the laptop is
running on battery, then there is no problem, and even if it's not,
the AC line voltage only gets as far as the "brick" power supply for
the laptop, and the DC voltage the brick supplies is too low to cause
- The power supply brick is mounted well above the water line, and
is attached to a bracket so it cannot be dislodged. (You can see it
at the far left edge of the picture, attached to the side of the
cabinet. It's a foot above the rim of the tub, and two or three feet
to the side.)
- The AC power cord for the "brick" is too short to permit it to
reach the water in any case. (It leads out of the left edge of the
picture, fastened snugly under the lip of the counter.)
- The power supply's AC cord is plugged into a Ground Fault Circuit
Interrupter (required on all modern bathroom outlets), and a GFCI
should, in theory, prevent a shock even if something like a hair dryer
falls into the water. (A GFCI shuts down the circuit in less than a
thousandth of a second if it senses even a tiny portion of the current
leaking to ground.)
- The other cords shown are for the mouse and the ethernet
connection to my Internet firewall. Both carry low voltage and low
The net result is that I have only one real risk: If I somehow
should tip the laptop into the water, Becky is certainly never
going to let me buy another one!
If you want to think about a REAL nasty situation, consider my
photo darkroom: Imagine standing on a wet concrete floor, in the dark,
one hand immersed in running water, groping with the other hand for
the switch of a 220-volt photo processor! A darkroom is a truly
wonderful way to electrocute oneself. There's a well-known
line about "There are old pilots, and there are bold pilots, but there
are no old bold pilots." I think the same sentiment could be applied
to darkroom technicians.
By the way, any GFCI has a "test" button to intentionally leak a
small amount of current and trip the circuit. If you have some
installed (and most people do, these days) get in the habit of pushing
those buttons every month or so, just for the heck of it.
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