At my local club we have pretty much the same definitions of hot and cold as above:
When a person wants to go downrange, they request permission to go " cold" and turn on the switch that turns on the red lights above each station. No one is allowed to touch a firearm when the range is cold - even to put it away.
Once the targets are changed, then they announce that the range is " hot " and the lights are turned off. Members may load and fire as they see fit.
You are the bows from which your children as living arrows are sent forth.