The Chairperson may at any time by notice require the owner of any permission on the ground floor of which any door, gate, bar, or window opens outwards upon a street or upon any land required for the improvement of a street in such manner, as in the opinion of the Chairperson, to obstruct the safe or convenient passage of the public along such street, to have the said door, gate, bar or window altered so as not to open outwards.