indoor smoking room exhaust

Hi, an occupant in our project building (office) insists on indoor smoking. He agreed to installing a cabin in his kitchenette (they already smoke there). The cabin is able to comply with LEED requirements (deck-to-deck-partition, 5Pa negative pressure). Additionaly the cabin filters the air through 3 filters: 1. F7 2.HEPA-filter H14 which filters particles down to 0.01µm 3. adsorption filter (activated carbon) removing smells and hazardous gases. It has been shown that the exhaust air contains less VOCs and hazardous substances from tabaco smoke than required by WHO for indoor air. Are we allowed to exhaust this thoroughly cleaned air to the outside within the 25ft? Thank you.