How long is a goalball game, and what happens if it is tied?

A game is two 12-minute halves with a 3-minute halftime break. A goal is worth one point.

IBSA's overview says tied games go to two three-minute golden-goal overtime periods, then penalty throws. A ten-goal difference in regulation ends the match under the mercy rule.

Sources: https://canadianblindsports.ca/goalball/about-the-game/ and https://ibsasport.org/sports/goalball/about/overview/