Section 27-324. Protection of structural members

Columns, girders, trusses,
  beams, lintels, etc. that are required to be fire  protected,  and  that
  support  only  one  floor  or a roof, and/or a non-bearing wall not more
  than one story high, shall be individually encased  on  all  sides  with
  materials  having  the  required  fire-resistance  rating;  or  shall be
  protected by a ceiling as specified in section 27-327  of  this  article
  having  the  required fire-resistance rating; or shall be protected by a
  combination of both a ceiling and individual encasement which, together,
  provide the required fire-resistance rating. Columns, girders,  trusses,
  beams,  lintels,  etc.  that are required to be fire protected, and that
  support more than one floor or support a bearing wall or wall more  than
  one  story  high,  shall  be individually encased on all sides for their
  entire  length  or   height   with   materials   having   the   required
  fire-resistance  rating.  Trusses  that  support only two stories or one
  story and a roof may be fire protected by an envelope  that  encompasses
  the entire truss with materials of the required fire-resistance rating.
    (a) Embedments and enclosures. Pipes, wires, conduits, ducts, or other
  service facilities shall not be embedded in the required fire protection
  of  a  structural  member  that  is required to be individually encased;
  except that pipes, wires, and conduits may be  installed  in  the  space
  between   the   required  fire  protection  and  the  structural  member
  protected, provided that where such facilities pierce the required  fire
  protection,  the area of the penetrations does not exceed two percent of
  the area of the fire protection on any one face,  the  penetrations  are
  closed  off  with  close-fitting  metal  escutcheons  or  plates and the
  concealed space shall be firestopped at each story  in  accordance  with
  the provisions of section 27-345 of article five of this subchapter.
    (b)  Impact  protection.  Where  the  fire  protective  covering  of a
  structural member is subject to impact damage from moving vehicles,  the
  handling of merchandise, or other activity, the fire protective covering
  shall  be protected by corner guards or by a substantial jacket of metal
  or other noncombustible material, to a height adequate to  provide  full
  protection.  Where  applicable,  such  protection  shall  be designed in
  accordance with the requirements of section 27-558 of article  three  of
  subchapter nine of this chapter.
    (c) Structural members in cavity walls. Where structural members occur
  within exterior cavity walls, portions of such structural members facing
  the  exterior need not be individually fire protected if the outer width
  of the cavity wall provides the required fire-resistance rating  and  is
  located  not  more  than  two  and  one-half inches from such structural
  members, and  if  all  surfaces  of  the  structural  members  are  fire
  protected  from  the  interior  of  the building by materials having the
  required fire-resistance rating.
    (d) Prestressing steel. Minimum covering of prestressing  steel  shall
  comply with the requirements of reference standard RS 5-15.
    (e) Exterior Exposed Structural Members. Structural members exposed to
  the  outdoors on buildings that do not exceed two stories or thirty feet
  in height, which are required by table 3-4  to  have  a  fire-resistance
  rating  not exceeding one hour, need not be protected on any face of the
  member that has an exterior separation of thirty feet or more,  provided
  the  outdoor area within the thirty feet separation distance is not used
  for storage of materials, or for motor vehicle parking.
    (f) Inspection of fire protection. The installation  of  all  required
  sprayed-on fire protection of structural members except those encased in
  concrete  shall  be subject to the controlled inspection requirements of
  section 27-132 of article seven of subchapter one of this code.
    (g)  Inspection  of  existing  sprayed-on   fire   protection   during
  alterations  in office spaces and in occupancy group E spaces. In office

  spaces and spaces classified in occupancy group E, where  an  alteration
  exposes  any  required sprayed-on fire protection of structural members,
  or where, pursuant to an alteration persons are  required  to  enter  or
  access  areas  in  which  such  sprayed-on fire protection is capable of
  being observed, the existing required spray-on fire protection shall  be
  subject  to  the controlled inspection requirements of section 27-132 of
  this code. Such controlled inspection shall require a determination  (i)
  that  the  existing  sprayed-on fire protection as originally applied or
  installed complies  with  the  applicable  requirements  of  this  code,
  including  those  for  installation  methods,  materials,  thickness and
  coverage; and (ii) that, since its original application,  the  integrity
  of  the  existing  sprayed-on  fire protection has not been compromised,
  damaged  or  displaced  by  the  current  alteration  or  by  any  prior
  alteration or other event.