If the nature of any work being done in a room or area is of such a character that dangerous or noxious dust, fumes, mists, gases, odors or other contaminants harmful to workers or occupants may get discharged, the ventilating requirements found in Table 18-28-403.3 shall be supplemented by using a local mechanical exhaust to remove the emission at its source, to prevent the escape of contaminants to the occupied space, and to discharge the mechanical exhaust to the outside atmosphere. Such mechanical exhaust shall be equipped with suitable means for the collection and removal of the contaminates. See Article 5, Exhaust Systems.