Section 199. Exemption from liability.

(1) No liability for pollution damage shall be incurred by the ship owner under this Chapter, if he proves that such damage,--- (a) resulted from an act of war, hostilities, civil war, insurrection or a natural phenomenon of an exceptional, inevitable and irresistible character; or (b) was wholly caused by any act or omission done with an intent to cause such damage by any person other than an employee or agent of the ship owner; or (c) was wholly caused by the negligence or other wrongful act of any Government or other authority responsible for the maintenance of lights or other navigational aids in the exercise of that function. (2) If the ship owner proves that the pollution damage resulted wholly or partially either from an act or omission done with intent to cause damage by the person who suffered the damage or from the negligence of that person, then, he shall be wholly or partially exonerated from his liability to such person.