Section 298 of the Principal Act is hereby amended by the substitution for paragraph (b) (as amended by section 19 of the Act of 1990) of subsection (12) of the following paragraph:
"(b) The Chief Appeals Officer may constitute, on the basis of districts or otherwise as he considers appropriate, panels of persons to sit as assessors with appeals officers and members may be selected in such manner as he may determine from such panels to so sit when any questionwhich, in the opinion of the Chief Appeals Officer, is appropriate for the assistance of assessors is heard.".