2006 New York Code - Liquefied Chlorine.

 
    § 27-4104 Liquefied chlorine. a. Permit required. It shall be unlawful
  to  store,  sell,  use  or  transport  any  liquefied chlorine without a
  permit.
    b. Certificate of fitness. It shall be unlawful to use  any  liquefied
  chlorine  except  under  the  constant supervision of a person holding a
  certificate of fitness.
    c. Compression. It shall be unlawful to compress any chlorine  gas  in
  the city.
    d.  Storage  and  use.  Liquefied  chlorine  gas may be stored only in
  quantities specified  by  the  commissioner,  and  under  the  following
  conditions:
    1. In approved fireproof buildings used exclusively for the storage of
  liquefied  chlorine.  Such building shall be designed and constructed in
  accordance with all applicable provisions of the building code.
    2. In enclosed lots or yards in  sparsely  settled  sections,  in  the
  discretion of the commissioner, and under such restrictions as he or she
  may deem necessary.
    3.  In buildings used for other purposes than the storage of liquefied
  chlorine, on the ground floor only, provided the containers of liquefied
  chlorine are located in a room or compartment constructed  of  fireproof
  or  fire  retarding material, which is easily accessible from the street
  or yard. If the room or compartment is not easily  accessible  from  the
  street  or  yard,  it  shall  be  provided  with  an  approved automatic
  sprinkler system by means  of  which  the  compartment  may  be  readily
  flooded  with  water,  all  of  which  shall be in accordance with plans
  approved by the commissioner. The  cylinders  of  chlorine  gas  may  be
  placed  in a receptacle, approved by the commissioner, so arranged as to
  be automatically flooded with cold water from a reliable source in  case
  of fire.
    4.  No  permit shall be issued for the use of liquefied chlorine above
  the grade floor, except  in  a  building  occupied  exclusively  by  the
  person,  firm  or  corporation using the liquefied chlorine and which is
  protected by an approved automatic sprinkler system.
    5. The number of liquefied gas cylinders  permitted  above  the  grade
  floor  shall  not in any case exceed in number twice the number actually
  connected and in use at  any  one  time,  and  the  cylinders  shall  be
  supported  from  the  ground  in  such manner as not to be dependent for
  support upon any non-fireproof portion of the building construction.
    6. No permit shall be issued for  the  storage  or  use  of  liquefied
  chlorine  in  any  building  used  for  a hotel, lodging house, tenement
  house, or dwelling, or in any building, lot or enclosure located  within
  fifty  feet  of  the  nearest wall of a building occupied as a hospital,
  school, theatre or other place of public amusement or assembly.
    e. Sale. It shall be unlawful to sell any liquefied chlorine  for  use
  within  the  city,  unless  the purchaser holds a permit to store or use
  liquefied chlorine.