A credit union may make loans to its directors, officers, credit committee members, and supervisory committee members, provided that the loan complies with all lawful requirements under this Act with respect to loans to other borrowers. No loan may be made to or cosigned by any director, officer, credit committee member, or supervisory committee member which would cause the aggregate amount of all loans then outstanding to or cosigned by all directors, officers, credit committee members, or supervisory committee members to exceed 20% of the unimpaired capital and surplus of the credit union.