NCIS concluded Al Amri had stood upon a folded bed mattress in order to reach the air vent to which he presumably attached the rope of his jerry-rigged noose (made from bed sheets).
ˌɛnsˌiːˌaɪˈɛs kəŋklˈuːdᵻd ˈæl ˈæmɹi hæd stˈʊd əpˌɑːn ɐ fˈoʊldᵻd bˈɛd mˈætɹəs ɪn ˈɔːɹdɚ tə ɹˈiːtʃ ðɪ ˈɛɹ vˈɛnt tʊ wˌɪtʃ hiː pɹɪzˈuːməbli ɐtˈætʃt ðə ɹˈoʊp ʌv hɪz dʒˈɛɹiɹˈɪɡd nˈuːs mˌeɪd fɹʌm bˈɛd ʃˈiːts.