Post Chief (sometimes PC or Observer) is the most senior grade of 'track' marshal (except for Examining Post Chiefs, who differ principally in that they are qualified to perform upgrade assessments for other grades)). Post chief may be used to refer both to the grade, and the role.
The pricipal role of a post chief, during track sessions, is to act as a Race Observer, a name by which they were formerly known. The post chief will report to race control anything which may be of interest to the clerk of the course. This may include rule infringements, potential hazards, and serious incidents.
The title was offically changed, by the MSA to 'Post Chief' to reflect their full set of responsibilities.
The post chief is the senior marshal on any individual post. They are responsible for ensuring that their team is fully prepared for the day. This includes ensuring that all marshals know what they should be doing, know how to be safe, are confident doing their particular role, or are being properly supervised by a more experienced marshal, and ensuring that all of the equipment required for the day is available.
Whilst post chief is a separate grade within the grading system, it is important to remember that any marshal may be asked to act as the post chief on any given day. It is not uncommon for a Flag marshal or Incident marshal to take on this role in the absence of a graded post chief.