In accordance with § 11 of the Act [§ 36 -310, D.C. Code, 1981 ed.] and § 2(1) of the Act [§ 36 -301(12), D.C. Code, 1981 ed.], the employer with the last known exposure shall be liable to pay compensation for occupational disease.
The employer shall not be liable for any occupational disease which results from a hazard to which the worker has had greater exposure outside of the employment.
D.C. Mun. Regs. tit. 7, r. 7-227