2006 New York Code - Designation Of Required Means Of Egress.

 
    §  27-389  Designation  of  required  means  of egress. (a) Except for
  spaces classified in  occupancy  J-2  and  J-3,  the  location  of  each
  required  means  of  egress  on  every floor of every structure shall be
  clearly indicated by exit signs. Such signs shall be placed at an  angle
  with the exit doorway if such placement shall be required for such signs
  to  serve  their purpose adequately. These signs shall be of an approved
  phosphorescent  material,  which  after  exposure  to  normal   lighting
  conditions shall be capable of remaining visible in total darkness for a
  period  of at least eight hours. They shall also be washable, non-toxic,
  non-radioactive, and if subjected to  fire  must  be  self-extinguishing
  when  the  flame  is  removed. Except for illuminated signs, these signs
  shall have a phosphorescent background and opaque text. Where  means  of
  egress were required to be indicated by an illuminated sign, there shall
  be  either  (1) an illuminated exit sign with the lettering thereon made
  of the approved phosphorescent material, or (2) a supplemental exit sign
  made of the approved phosphorescent material with an  opaque  text,  and
  placed adjacent to or as close as possible to such illuminated sign.
    (b)  Except  for spaces classified in occupancy groups J-2 and J-3, in
  long corridors, in open floor areas and in all  other  situations  where
  the  location  of  the means of egress may not be readily discernible or
  understood by the occupants, directional signs  shall  be  provided  and
  maintained  to  serve  as  guides  from  all  portions  of  the floor or
  corridor. These signs shall be of an  approved  phosphorescent  material
  which  after  exposure to normal lighting conditions shall be capable of
  remaining visible in total darkness for  a  period  of  at  least  eight
  hours.  They  shall also be washable, non-toxic, non-radioactive, and if
  subjected to fire must be self-extinguishing when the flame is  removed.
  Except  for  illuminated  signs  these signs shall have a phosphorescent
  background and opaque text. Where a directional sign was required to  be
  illuminated  there  shall  be either (1) an illuminated directional sign
  with the lettering, indicator, symbol or other device  thereon  made  of
  the aforesaid phosphorescent material, or (2) a supplemental directional
  sign  with the same lettering, indicator, symbol or device as appears on
  the illuminated sign, but opaque, on a background made of the  aforesaid
  phosphorescent  material  and placed adjacent to or as close as possible
  to such illuminated sign.
    (c) Except where otherwise permitted by the provisions of any law, the
  lettering of exit signs shall be of letters of  at  least  eight  inches
  high.
    (d) In those buildings not provided with artificial lighting, in those
  buildings  which  maintain  one  or more auxiliary systems for emergency
  exit lighting in the event of a public utility  failure,  and  in  those
  buildings  for  which  the  installation  of  one or more such auxiliary
  systems is  commenced  on  or  before  August  sixth,  nineteen  hundred
  sixty-nine,  the  signs  need  not be phosphorescent but shall otherwise
  conform to this section.