37. The Board shall in the following circumstances have an absolute discretion to dismiss an appeal—

(a) where, having considered the grounds of appeal, the Board is of opinion that the appeal is vexatious, frivolous or without substance or foundation, or

(b) where, having regard to—

(i) the nature of the appeal (including any question which in the Board's opinion is raised by the appeal), and

(ii) any previous decision of a building control authority or the Board which in its opinion is relevant,

the Board is satisfied that in the particular circumstances the appeal should not be further considered by it.