Musannaf Ibn Abi Shayba 13:1096

Abu Bakr narrated to us, he said: Abd al-A’la narrated to us, from Yunus, from al-Hasan, that he said regarding the fuller (laundryman): If he ruins [the garment], he is liable. He said: And he (al-Hasan) would not hold him liable for drowning, nor burning, nor an overpowering enemy.