Well have to concurr with everyone dont do it.
HF Radios still give you a boot if you grab the antenna, regardles if it was oldvalve powered or modern transistorised output Power amplifier.
The RF energy emmited also can be picked up by other antenni ( anything piece of wire dental filling even)
in the immediate area, induce a voltage and discharge, causing you guessed it, a spark.
Youll notice that refuellers dont carry phones or Radios, or they shouldnt for this reason. Same reason for putting petrol in you car at the gas station, ( no cell phones).
When I was a techo in the RAAF, I serviced a multitude of different radios and everyone of them, when keyed, would trip the earth leakage circuit breakers power outlets, on the bench.
Food for thought
Regards
Sheep
P.S. During my training in the RAAF in LAVERTON VIC, we took a PRC-47 HF SET out bush and did some exersises. We used the conventional antenna inverted V and adjusted the wavelength. But we also used other objects. Like an old Barbwire fence and even a wet tree. Pretty robust stuff the old HF. Both execisises worked and we talked to our base in the School.