Section 27-827. General requirements

For the purpose of this subchapter fuel
  oil  shall mean hydrocarbon oils as classified in reference standards RS
  14-3 and RS 14-12 and shall have a flashpoint not lower than one hundred
  degrees Fahrenheit when tested in accordance with reference standard  RS
  14-13  and  marketed under the following commercial grades: range oil or
  no. 1 fuel oil; diesel oil or no. 2 fuel oil; no. 4 fuel oil; no. 5 fuel
  oil; no. 6 fuel oil. Except as provided in section 27-4056 of this title
  the use of crankcase  refuse  oil  as  fuel  oil  is  prohibited.  These
  requirements shall not apply to (1) the use and installation of portable
  burners  not  requiring a connection to a flue where such burners are of
  the type commonly used for household purposes such as  oil  stoves,  oil
  heaters and oil lamps equipped with a woven wick; (2) portable apparatus
  such  as  blow torches, soldering pots, tar heaters, snow melters, etc.;
  (3) storage tanks for oils used in industrial process such as  cracking,
  distilling,  manufacture  of  gas,  or  other similar processes. For the
  requirements governing the storage of such oils see chapter four of this
  title.