Section 718.305 - Presumption of pneumoconiosis(a)Applicability. This section applies to all claims filed after January 1, 2005, and pending on or after March 23, 2010.(b)Invocation.(1) The claimant may invoke the presumption by establishing that-(i) The miner engaged in coal-mine employment for fifteen years, either in one or more underground coal mines, or in coal mines other than underground mines in conditions substantially similar to those in underground mines, or in any combination thereof; and(ii) The miner or survivor cannot establish entitlement under § 718.304 by means of chest x-ray evidence; and(iii) The miner has, or had at the time of his death, a totally disabling respiratory or pulmonary impairment established pursuant to § 718.204 , except that § 718.204(d) does not apply.(2) The conditions in a mine other than an underground mine will be considered "substantially similar" to those in an underground mine if the claimant demonstrates that the miner was regularly exposed to coal-mine dust while working there.(3) In a claim involving a living miner, a miner's affidavit or testimony, or a spouse's affidavit or testimony, may not be used by itself to establish the existence of a totally disabling respiratory or pulmonary impairment.(4) In the case of a deceased miner, affidavits (or equivalent sworn testimony) from persons knowledgeable of the miner's physical condition must be considered sufficient to establish total disability due to a respiratory or pulmonary impairment if no medical or other relevant evidence exists which addresses the miner's pulmonary or respiratory condition; however, such a determination must not be based solely upon the affidavits or testimony of any person who would be eligible for benefits (including augmented benefits) if the claim were approved.(c)Facts presumed. Once invoked, there will be rebuttable presumption- (1) In a miner's claim, that the miner is totally disabled due to pneumoconiosis, or was totally disabled due to pneumoconiosis at the time of death; or(2) In a survivor's claim, that the miner's death was due to pneumoconiosis.(d)Rebuttal - (1)Miner's claim. In a claim filed by a miner, the party opposing entitlement may rebut the presumption by-(i) Establishing both that the miner does not, or did not, have:(A) Legal pneumoconiosis as defined in § 718.201(a)(2) ; and(B) Clinical pneumoconiosis as defined in § 718.201(a)(1) , arising out of coal mine employment (see§ 718.203 ); or(ii) Establishing that no part of the miner's respiratory or pulmonary total disability was caused by pneumoconiosis as defined in § 718.201 .(2)Survivor's claim. In a claim filed by a survivor, the party opposing entitlement may rebut the presumption by-(i) Establishing both that the miner did not have:(A) Legal pneumoconiosis as defined in § 718.201(a)(2) ; and(B) Clinical pneumoconiosis as defined in § 718.201(a)(1) , arising out of coal mine employment (see§ 718.203 ); or(ii) Establishing that no part of the miner's death was caused by pneumoconiosis as defined in § 718.201 .(3) The presumption must not be considered rebutted on the basis of evidence demonstrating the existence of a totally disabling obstructive respiratory or pulmonary disease of unknown origin.78 FR 59114, Sept. 25, 2013