“Purifying filter acronym” crossword clue

Reveal the answer to see why it works and where this clue has appeared before.HEPA is the answer to the New York Times crossword clue “Purifying filter acronym”. It was last seen in the puzzle of September 26, 2025, where it runs at 51 Down and fills 4 squares. It crosses 4 other entries in that grid — those are listed below and are the quickest way to confirm the letters you already have. This exact clue has run 2 times in NYT puzzles, first on September 26, 2025.