Ashes, smoldering coals, or embers, greasy or oily substances
and other matter liable to cause spontaneous ignition shall not be
deposited or allowed to remain within 10 feet of any combustible materials,
except in metal or other noncombustible receptacles. Such receptacles
shall be placed on noncombustible stands, unless resting on a noncombustible
floor or on the ground outside the building and shall be kept at least
two feet away from any combustible wall or partition.