Ga. Code § 34-9-284
Where compensation is payable for an occupational disease, the employer in whose employment the employee was last injuriously exposed to the hazards of such disease and the insurance carrier, if any, by whom the employer was insured when such employee was last so exposed under such employer shall alone be liable therefor, without right of contribution from any prior employer or insurance carrier. The amount of the compensation for any occupational disease shall be based upon the average weekly wages of the employee, as determined under Code Section 34-9-260. The date upon which the employee first suffers disablement from the occupational disease or the last date the employee was employed by any employer, whichever date would provide the higher average weekly wage for such employee, shall be deemed the date of the injury for the purpose of determining the average weekly wage; and the notice of injury and claim for compensation, as required by Code Sections 34-9-80 through 34-9-82, 34-9-85, and 34-9-86, shall be given and made to such employer.
OCGA § 34-9-284