the black box warning

 Seeing a printed warning in a black box is never good these days, usually on medications or cigarettes.  Black Box = THIS IS SERIOUS, PAY ATTENTION

N2CQR posted this black box warning

May 1939 QST

 on his Soldersmoke blog:  

http://soldersmoke.blogspot.com/2022/06/soldersmoke-podcast-238-solder-smoke.html

And what prompted the 1939 article with the black box warning were the deaths in 1938 of both Ross Hull (QST editor) and Phil Murray.

I've gotten stunned by high voltage in the HW-16

In the 21st century these deaths would be a lot less likely.  Why ?  Ground Fault Circuit Interrupters for one thing.  Also, most gear is low voltage (50 volts seems like a good dividing line between low and high voltage).  And finally, people seem scared to fix their own stuff, not so much because of electrocution but because of the money invested in the gear.

In reality we are all just containers of salty (conductive) fluid.  Puncture that outer container, add voltage and a path to ground and electrocution is still possible.

In July of 1939 QST announced the winner of their safety slogan:  Switch to Safety.

  It isn't mentioned as much recently, probably due to the reasons above, but still true.  

However, a slogan isn't a system, safety instruction coupled with protection circuits are the way to prevent shock and electrocution.  

I can remember the president of our high school radio club talking about "fusing for safety" which I didn't quite understand at the time (1972 or so).  I *think* he meant ground fault circuit interruption.  In high school I lived in a house with fuses (actually Fuse-stats), 2 wire outlets, I *think* the ground connection to the steel outlet boxes was via that spiral of steel around BX cabling.  Not a super great situation.

In this house I live in now there is a ground fault breaker for the bath and for outside/garage outlets.  I have always meant to add ground fault interrupter outlets to the basement and to my "lab".  Of course there probably are rare situations where a person could still be electrocuted even with the ground fault interrupter, if the current flow is from line to neutral and your body is in that loop, look out.  That's where those black box rules still apply !

There was a good article by KC7O in the March 2019 QST (page 36) titled: Improve Workbench Safety with GCFI and a Kill Switch).  I do have an uninstalled GCFI so I may try out the ideas.

Also, nuisance trips can be an issue with GCFI.  If there are too many of them the ground fault protection may be taken out, kind of the 21st century equivalent of putting a penny in the fusebox. see:

http://arrl.org/gfci-and-afci-devices 

I don't know much about the Arc Fault Circuit Interrupters, they can sense arcing on the circuit and shut it down.  Arcing can cause fires.

The consistent ground fault breaker nuisance trip I have is whenever there is lightning (big arc!) in the area the breaker will trip.  When we had a freezer in the garage this could cause trouble, so I added a simple battery powered plug-in audio oscillator that would scream if the outlet ever went dead.

One potential problem with ground fault circuit interrupters is kinda like the massive new helmets used in the NFL during training camp this year.  Both the new helmets and GFCI may promote a sense of invincibility where the rules don't apply to you - they do !

Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm