10.1. For the purposes of subparagraph 5 of the first paragraph of section 10, a disability is severe only if by reason thereof the person is incapable regularly of pursuing any substantially gainful occupation.
However, in the case of a person 60 years of age or over, a disability is severe if by reason thereof the person is incapable regularly of carrying on the substantially gainful occupation he holds at the time he ceases to work owing to his disability.
A disability is prolonged only if it is likely to result in death or to be of indefinite duration.