This is how they clean electrical boxes safely (HFE solution) Looks Damaging

[SirRahX]

 

[DWBass]

Most likely an unplugged, unused box being washed down.

 

[An RnB Thug]

It's ON and they are using a Dielectric Liquid to clean the unit (NOT WATER)
The liquid does not conduct electricity so it's harmless to circuits and moving parts
#YourWelcome