2006 New York Code - Incinerator Chimney Connectors.

 
    §  27-878  Incinerator  chimney  connectors. (a) The chimney connector
  from the combustion chamber of an auxiliary fuel-fired incinerator shall
  be constructed of metal at  least  as  heavy  as  no.  16  manufacturers
  standard  gauge  when  twelve  inches  or  less  in  diameter or greater
  dimension, and of metal at  least  as  heavy  as  no.  12  manufacturers
  standard  gauge  when  they  exceed twelve inches in diameter or greater
  dimension.
    (b) Chimney connectors from auxiliary fuel-fired incinerators shall be
  lined with firebrick, laid  in  fire  clay  mortar,  at  least  two  and
  one-half  inches  thick when they are between twelve inches and eighteen
  inches in diameter or greater dimension and at least four  and  one-half
  inches  thick  when  they  are  larger;  where  no  flue gas temperature
  reduction is effected the chimney connectors shall be  equipped  with  a
  guillotine  or horizontal sliding damper or butterfly damper interlocked
  with the fuel firing controls  so  that  operation  of  the  incinerator
  occurs  when  the  damper  is open. If chimney connectors from auxiliary
  fuel-fired incinerators lead into and combine  with  chimney  connectors
  from other equipment, the connectors from the other equipment shall also
  be   lined   as   required   for  direct  flue  connections  unless  the
  cross-sectional area of the connector into which they lead is  at  least
  four times their required cross-sectional area.
    (c)  Chimney  connectors  for an auxiliary fuel-fired incinerator to a
  boiler stack or chimney for a high temperature heating  equipment  shall
  be  permitted  when the cross-sectional area of such stack or chimney is
  at least four times that of the incinerator chimney connector.
    (d) The clearance of incinerator chimney connectors  from  combustible
  material  or  construction  shall  be  at  least. thirty-six inches This
  clearance may be reduced as outlined in table 15-8  in  accordance  with
  the   type   of  protection  applied  to  the  combustible  material  or
  construction.