*72Dissenting Opinion by
Judge Mencer:I respectfully dissent.
Section 311 of The Pennsylvania Workmen’s Compensation Act (Act), Act of June 2, 1915, P.L. 736, as amended, 77 P.S. §631, insofar as applicable to occupational disease claims, requires that an employee notify his employer of his disability within 120 days of the date that the employee (1) becomes disabled and (2) knows or in the exercise of reasonable diligence should know of the possible relationship between the disability and his employment. McManus v. Rochester & Pittsburgh Coal Co., 29 Pa. Commonwealth Ct. 91, 368 A.2d 1365 (1977).1 Since the referee failed to make findings on either of these issues, I would remand.
With regard to when the claimant “became disabled,” the referee found that he became totally disabled on September 27, 1974, the date claimant was told by a physician that he was totally disabled due *73to coal worker’s pneumoconiosis. The referee made no finding concerning when the claimant became partially disabled. It could be argued that, under the circumstances of this case, the term “disability” in Section 311 should be construed to mean “total disability” and not “partial disability,” in which case the referee’s finding would be adequate. Cf. Rakoczy v. Jandy Coal Co., 26 Pa. Commonwealth Ct. 459, 363 A.2d 1338 (1976) (where claimant is seeking benefits for total disability, liability of Commonwealth under Section 305.1 of the Act, 77 P.S. §411.1, is determined by reference to date of total disability). However, the purpose of the notice requirement is to protect the employer against claims made after opportunity for a full and complete investigation has passed, and the logical triggering event is therefore “a claimant’s knowledge of his physical inability to work and its possible relationship to his employment.” Garden Coal Co. v. Workmen’s Compensation Appeal Board, 27 Pa. Commonwealth Ct. 568, 573 n. 4, 367 A.2d 360, 363 n. 4 (1976) (emphasis in original).2 That is, when an employee knows or should know that he has a claim for compensation, notice should be given to the employer within 120 days to allow for as complete an investigation as possible, and the fact that the employee may not know for certain whether he is totally or only partially disabled should not relieve him of this obligation. In this case, claimant’s testimony, although somewhat confusing, would allow the factfinder to infer that claimant was at least *74partially disabled when be left bis job on February 14,1974.3
Since we cannot infer from tbe referee’s award of benefits that tbe issues set forth in tbe first paragraph of this dissent were resolved in claimant’s favor, see Page’s Department Store v. Velardi, 464 Pa. 276, 346 A.2d 556 (1975), I would remand to allow tbe referee to make tbe necessary findings of fact.
President Judge Bowman joins in this dissent.Section 311 provides as follows :
Unless the employer shall have knowledge of the occurrence of the injury, or unless the employe or someone in his behalf, or some of the dependents or someone in iheir behalf, shall give notice thereof to the employer within twenty-one days after the injury, no compensation shall be due until such notice be given, and, unless such notice be given within one hundred and twenty days after the occurrence of the injury, no compensation shall be allowed. However, in cases of injury resulting from ionizing radiation or any other cause in which the nature of the injury or its relationship to the employment is not known to the employe, the time for giving notice shall not begin to run until the employe knows, or by the exercise of reasonable diligence should know, of the existence of the injury and its possible relationship to his employment. The term ‘injury’ in this section means, in cases of occupational disease, disability resulting from occupational disease. (Emphasis added.)
In Garden Coal, wo also made it clear that the issue of notice under Section 311 is entirely distinct from the issue of apportionment of liability under Section 305.1 and that the term “disability” must be constraed with reference to the underlying purpose of the particular section involved. 27 Pa. Commonwealth Ct. at 572-73 n. 4. 367 A.2d at 362-63 n. 4.
On direct examination, claimant testified that he was first advised of his condition on September 27, 1974. On cross-examination, however, the claimant testified that prior to January 1973 he had been told by his family physician that his breathing difficulties were attributable to his work in the coal mines. The fact that- claimant applied for and was awarded federal black lung-benefits in 1973, although not controlling as a matter of law, is nevertheless a factor for the referee to consider in resolving the apparent inconsistency in the claimant’s testimony. See Jones & Laughlin Steel Corp. v. Workmen’s Compensation Appeal Board, 35 Pa. Commonwealth Ct. 610, 387 A.2d 174 (1978).