(a) The hearing officer or the commission may take official notice of a fact not subject to reasonable dispute if it is either generally known or can be accurately and readily verified in generally accepted references prior to or following the close of the hearing record.

(b) If the hearing officer or the commission intends to take official notice of a material fact not appearing in the hearing record and of which judicial notice could not be taken, every party shall be given notice and an opportunity to dispute the fact and its materiality.