Section 21.63 - Housekeeping Practices(1) Highly inflammable, volatile liquids or solutions shall not be used for cleaning purposes.(2) No person shall use volatile liquids for cleaning purposes unless such cleaning operations are conducted in an outside and remote area, or in a room or building specifically set aside for such operations, which room or building shall be properly ventilated, fireproofed and equipped with adequate readily accessible fire extinguishing apparatus in accordance with the rules of the National Board of Fire Underwriters.(3) Discarded inflammable liquids shall be properly contained and labeled as may be required and shall be removed by the lessee from the Airport each day.(4) Lessees of hangars or other aircraft servicing or maintenance buildings, terminal buildings or ramps and apron areas shall provide suitable metal receptacle with self-closing lids for the storage of oily wastes, rags and all other combustible rubbish or trash. All such materials shall be disposed of by the lessee off of the Airport each day.(5) All lessees on the Airport shall keep the floors of hangars or other building or ramp and apron areas free and clear of oil, grease and other inflammable materials. The floors of hangars and other buildings and ramps and apron areas shall be cleaned daily and kept free of rags, waste material or other trash.(6) Any person causing overflow or spillage of any petro-chemical, oil or grease on any apron area shall be responsible for cleaning such area.(7) No petroleum or petro-chemical products or objectionable industrial waste matter shall be dumped or be permitted to drain into drainage ditches, gutters, bodies of water or into sewer systems or storm drains.