How to say “Something above my bed keeps rattling; could it be the escape hatch?” in Japanese

In Japanese

ベッドの上(うえ)でずっとカタカタいってるけど、非常脱出(ひじょうだっしゅつ)ハッチの音(おと)かな？

Beddo no ue de zutto katakata itteru kedo, hijō dasshutsu hatchi no oto kana?