▁fl ame ▁ret ard ant ▁which ▁belongs ▁to ▁the ▁group ▁of ▁poly b rom in ated ▁di phen yl ▁eth ers ▁( P B DE s ). ▁ ▁Com position , ▁uses , ▁and ▁production ▁Com mer cial ▁oct a B DE ▁( also ▁known ▁as ▁" Oct ab rom ") ▁is ▁a ▁technical ▁mixture ▁of ▁different ▁P B DE ▁con gen ers ▁having ▁an ▁average ▁of ▁ 7 . 2 ▁to ▁ 7 . 7 ▁b rom ine ▁atoms ▁per ▁mole c ule ▁of ▁di phen yl ▁ ether . ▁ ▁The ▁pre domin ant ▁con gen ers ▁in ▁commercial ▁oct a B DE ▁are ▁those ▁of ▁he pt ab rom odi phen yl ▁ ether ▁and ▁oct a B DE . ▁The ▁term ▁oct a B DE ▁alone ▁refers ▁to ▁is om ers ▁of ▁oct ab rom odi phen yl ▁ ether ▁( P B DE ▁con gener ▁numbers ▁ 1 9 4 – 2 0 5 ). ▁ ▁Only ▁con gen ers ▁with ▁more ▁than ▁ 1 % ▁listed . ▁ ▁Oct a B DE ▁is ▁used ▁in ▁conj unction ▁with ▁ant im ony ▁tri ox ide ▁as ▁a ▁fl ame ▁ret ard ant ▁in ▁the ▁hous ings ▁of ▁elect rical ▁and ▁electronic ▁equipment , ▁mainly ▁in ▁the ▁pl astic ▁ac ry lon it rile ▁but ad iene ▁sty rene , ▁but ▁also ▁in ▁high ▁impact ▁pol yst y rene , ▁poly but yl ene ▁t ere ph th al ate ▁and ▁poly am ides . ▁Typ ically ▁ 1