Question about Gas Discharge Tube

It's defined right there on the page:

DC Sparkover 100 V/s (slow rate of rise of voltage) Impulse Sparkover 100 V/?s (fast rate of rise of voltage) Impulse Sparkover 1000 V/?s (very fast rate of rise of voltage) Impulse Transverse Delay 1000 V/?s (time to fire with very fast rate of rise of voltage?)

I never use a GDT so I have a hard time to understand the word literally. I guess the question should be: what is the definition of Sparkover, Impulse Sparkover and Impulse Transverse Delay for non-engineer?

Thanks

"?s" should read uS or microsecond or millionth of a second. A rate of rise of voltage of 100 volts per second is quite slow - if it was a lamp you would see it change.

A rate of rise of voltage of 100 volts per millionth of a second is very fast.

A rate of rise of voltage of 1000 volts per millionth of a second is very fast indeed - in one second you go from zero volts to 1000,000,000 volts (one billion volts).

I hope this helps.