Section 8(1)(a) of the Refugee Act, 1996 (as amended) provides that a person who arrives at the frontiers of the State seeking asylum or the protection of the State against persecution or requesting not to be removed or returned to a particular country may apply to the Minister for a declaration of refugee status.
Any person who makes an asylum application at a port of entry must be given permission to enter and remain in the State until their application for international protection is determined.
I am not aware of any instance where a person seeking the State's protection has been refused entry at a port.