R602.8 Fireblocking required. Fireblocking shall be provided
to cut off all concealed draft openings (both vertical and horizontal)
and to form an effective fire barrier between stories, and
between a top story and the roof space. Fireblocking shall be
provided inwood-frame construction in the following locations.
1. In concealed spaces of stud walls and partitions, including
furred spaces and parallel rows of studs or staggered
studs; as follows:
1.. Vertically at the ceiling and floor levels.
2. At all interconnections between concealed vertical and
horizontal spaces such as occur at soffits, drop ceilings
and cove ceilings.
3. In concealed spaces between stair stringers at the top and
bottom of the run. Enclosed spaces under stairs shall
comply with Section R311.2.2.
4. At openings around vents, pipes, ducts, cables and wires
at ceiling and floor level, with an approved material to
resist the free passage of flame and products of combustion.
5. For the fireblocking of chimneys and fireplaces, see Section
R1003.19.
2.3. Return-air inlets shall not be located
within 10 feet (3048 mm) of any appliance
firebox or draft hood in the same
room or space.
3. Rooms or spaces containing solid-fuel burning
appliances, provided that return-air inlets are
located not less than 10 feet (3048 mm) from
the firebox of such appliances.
M1801.5 Mechanical draft systems. A mechanical draft system
shall be used only with appliances listed and labeled for
such use.
M1801.9 Fireblocking. Vent and chimney installations shall
be fireblocked in accordance with Section R602.8.
M1801.10 Unused openings. Unused openings in any venting
system shall be closed or capped.
3. Connectors serving appliances operating under a natural
draft shall not be connected to any portion of a mechanical
draft system operating under positive pressure.
3302.2 Penetrations of fire-resistance-rated assemblies.
Installations in hollow spaces, vertical shafts and
ventilation or air-handling ducts shall be made so that the possible
spread of fire or products of combustion will not be substantially
increased. l penetrations through
fire-resistance-ratedwalls, partitions, floors or ceilings shall be
protected by approved methods to maintain the fire-resistance
rating of the element penetrated.
