Dreams of Danger

There is a kind of dream that is perpetually the same.   The details and the setting might vary, but the whole dream, the nightmare, pivots on fear.  Something is after you!  Whether chased by a lion and leaping headlong into water, careening around a curve in a car while pursued by men with guns, or bursting through a door while a swarm of yellow jackets churn around you—you awaken with a gasping lurch. 

Late last night I awakened with such a lurch, braced for catastrophe.  Oddly, I could not vividly recall what horror propelled me to my fearful, awakened state.  The nearest panicky experience that might compare to this to in my waking world is one that occurs on occasion while I am working.  The dangers of my work as an electrician are certainly real.  Though fall accidents and receiving an electric shock are obvious dangers, the most lethal accidents are arc blast incidents.  These often do not involve electric shock at all.

Arc blast (commonly called arc flash) incidents occur at the points in electrical circuits where ground faults or short circuits appear.   The explosive forces are determined by the available fault-current amperage for any certain point on an electrical system and escalate in an exponential fashion the nearer they get to the point of electrical service from the power provider.  If, as an illustration, we thought of the available current flow at a wall receptacle as an equivalent of the flow of water from an open garden hose, the flow available at the service panel would then compare to a fully opened fire hydrant.  The fault currents available at the nearest office building service might be a waterfall.

But this is not cool water pouring out from our electrical circuits.  The temperatures reached at the point of fault are hotter than those reached on the surface of the sun.  Metal vaporizes and spews forth.  Sparks and smaller parts eject from the faulted equipment like stray bullets.  Magnetic forces and sound waves ripple outward.   People sometimes perish at these points without ever having received an electric shock.

On a few occasions, while punching holes for conduits in the top of live electrical service equipment enclosures, I have inadvertently created instants like those when I wake from my nearly-caught dreams.  On those occasions, my drill has suddenly twisted through the metal and dragged me nearly inside, and then, just as I brace to stop, the metal bit releases from the drill and falls free inside the live equipment.

Stop here.                                                             

Inside the equipment 70,000 amps crouch, waiting to release should the bit fall across live bussing or exposed lugs.  Consider: a fraction of a single amp is enough to kill by contact.  20,000 amps can launch me into orbit.  My drill bit might trigger an explosive fault.

For an instant, I freeze.  In less than a second, I will either be surrounded by silence or sprawled across sizzling ruins.

Awake!

 

--Mitchell Hegman