Order to be explained orally

if the person making such objection be present at the office of the Board, the said order shall be explained to him orally, and such order cannot be so explained, notice of such order shall be served as provided in Section 307 on the person making the objection; and such explanation of, or service of, the notice of the said order shall be deemed a requisition duly made under this Act to execute the work or do the thing required.