Years of wage-loss occurring prior to normal retirement age that are the result of a covered illness contracted by a covered Part E employee through work-related exposure to a toxic substance at a Department of Energy facility or a RECA section 5 facility, as appropriate, may be compensable under Part E of the Act. Whether years of wage-loss are compensable depends on determinations with respect to:

(a) The average annual wage of the employee as determined by OWCP in accordance with § 30.810;

(b) The percentage of his or her average annual wage that the employee was able to earn during the calendar year(s) in question as determined by OWCP in accordance with § 30.811; and

(c) Whether the employee's inability to earn at least as much as his or her average annual wage was due to a covered illness as defined in § 30.5(s).