Permit the reconstruction of a nonconforming building which has been damaged by explosion, fire, act of God, or the public enemy, to the extent of more than fifty percent (50%) of its fair market value, where the Board finds some compelling necessity requiring a continuance of the nonconforming use and primary purpose of continuing the nonconforming use is not to continue a monopoly, and provided such reconstruction does not, in the judgment of the Board prevent the return of the property to a conforming use or increase the nonconformity of a nonconforming structure beyond what is permitted by Section 31 of this ordinance. Such actions of the Board shall have due regard for the property rights of persons affected when considered in the right [light] of public welfare, the character of the area surrounding such structure and the conservation, preservation and protection of surrounding properties and their values.