A person in a gathering commits a summary offense if he refuses to obey a reasonable official request or order to move:
to prevent obstruction of a highway or other public passage; or
to maintain public safety by dispersing those gathered in dangerous proximity to a fire or other hazard.
An order to move, addressed to a person whose speech or other lawful behavior attracts an obstructing audience, shall not be deemed reasonable if the obstruction can be readily remedied by police control of the size or location of the gathering.
As used in this section the word obstructs means renders impassable without unreasonable inconvenience or hazard.