How do head injury (HIA) and blood replacements work in a Test?

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Accepted Answer

Both are temporary replacements under World Rugby Law 3. Head Injury Assessment (HIA) (in matches World Rugby has approved in advance for the HIA process) The player leaves the field and is temporarily replaced, even if all the replacements have been used. Play can't restart until the replacement is on. If the player isn't back within 12 minutes (actual time), the replacement becomes permanent. If the player also has a blood injury, up to 5 minutes can be taken to stop the bleeding before the 12 minutes start. Blood injury The player goes off and may be temporarily replaced until the bleeding is controlled or covered. If not back within 15 minutes (actual time), the replacement becomes permanent. In international matches, the match-day doctor decides whether it is a blood injury. Concussion A player who is concussed or has suspected concussion must be immediately and permanently removed ("Recognise and Remove") and cannot return to that match.