On a film set, this title is for the first assistant to the head electrician
In the 
motion picture industry and on a television crew, a GAFFER is the head 
electrician, ... are first assistant cameramen placing marks around the set or 
location and... [DOC] [TLE] Crew Jobs: Every Film Crew Position and Job Description [PAR] Nov 30, 2014 ... Production Assistant  assists the first assistant director with set ... or crane; work 
closely with the electrical department to put in lighting set ups... [DOC] [TLE] 11 Strange Movie Job TitlesExplained!