CREATE TABLE table_44091 ("Usage" CLOB, "Class" CLOB, "Performance" CLOB, "Performance test" CLOB, "Particulate size approaching 100% retention" CLOB, "Test Standard" CLOB)

Which Performance has a Test Standard of bs en779, and a Particulate size approaching 100% retention of >2 m, and a Class of f6?
SELECT "Performance" FROM table_44091 WHERE "Test Standard" = 'bs en779' AND "Particulate size approaching 100% retention" = '>2µm' AND "Class" = 'f6'
SELECT "Performance" FROM "table_44091" WHERE "Class" = 'f6' AND "Particulate size approaching 100% retention" = '>2µm' AND "Test Standard" = 'bs en779'