Black Mesa is the fictional research facility in Valve's Half-Life series, first released in 1998, where an experiment opens a portal to another dimension. Its alarm tones became familiar to players from tense escape sequences and were later remixed in the fan remake also called Black Mesa. Clips of the fast alarm spread on soundboards alongside other gaming alerts like the danger alarm sound effect meme, and creators now reuse the loop far outside the games as a universal signal for scientific disasters and urgent evacuations.