(a) In addition to the compensation benefits provided by section 31-308 for specific loss of a member or use of the function of a member of the body, or any personal injury covered by this chapter, the administrative law judge, after such payments provided by said section 31-308 have been paid for the period set forth in said section, may award additional compensation benefits for such partial permanent disability equal to seventy-five per cent of the difference between the wages currently earned by an employee in a position comparable to the position held by such injured employee prior to his injury, after such wages have been reduced by any deduction for federal or state taxes, or both, and for the federal Insurance Contributions Act in accordance with section 31-310 , and the weekly amount which such employee will probably be able to earn thereafter, after such amount has been reduced by any deduction for federal or state taxes, or both, and for the federal Insurance Contributions Act in accordance with section 31-310 , to be determined by the administrative law judge based upon the nature and extent of the injury, the training, education and experience of the employee, the availability of work for persons with such physical condition and at the employee's age, but not more than one hundred per cent, raised to the next even dollar, of the average weekly earnings of production and related workers in manufacturing in the state, as determined in accordance with the provisions of section 31-309 . If evidence of exact loss of earnings is not available, such loss may be computed from the proportionate loss of physical ability or earning power caused by the injury. The duration of such additional compensation shall be determined upon a similar basis by the administrative law judge, but in no event shall the duration of such additional compensation exceed the lesser of (1) the duration of the employee's permanent partial disability benefits, or (2) five hundred twenty weeks. Additional benefits provided under this section shall be available only to employees who are willing and able to perform work in this state.
(b) Notwithstanding the provisions of subsection (a) of this section, additional benefits provided under this section shall be available only when the nature of the injury and its effect on the earning capacity of an employee warrant additional compensation.