28 C.F.R. § 79.4

(a) The claimant, eligible surviving beneficiary, or beneficiaries bear the burden of providing evidence of the existence of each element necessary to establish eligibility under any compensable claim category set forth in § 79.3(a).

(b) In the event that reasonable doubt exists with regard to whether a claim meets the requirements of the Act, that doubt shall be resolved in favor of the claimant or eligible surviving beneficiary.

(c) Written affidavits or declarations, subject to penalty for perjury, will be accepted only for the following purposes:

(1) To establish eligibility of family members as set forth in § 79.71(e), (f), (g), (h), or (i);

(2) To establish other compensation received as set forth in § 79.75(c) or (d);

(3) To establish employment in a uranium mine, mill or as an ore transporter on the standard claim form in the manner set forth in §§ 79.43(d), 79.53(d) and 79.63(d), respectively; and

(4) To substantiate the claimant's uranium mining employment history for purposes of determining working level months of radiation exposure by providing the types of information set forth in § 79.43(d), so long as the affidavit or declaration:

(i) Is provided in addition to any other material that may be used to substantiate the claimant's employment history as set forth in § 79.43;

(ii) Is made subject to penalty for perjury;

(iii) Attests to the employment history of the claimant; and

(iv) Is made by a person other than the individual filing the claim.