Summary of NFPA 101 Interior Finish
Requirements
• Because of the significant impact wall and ceiling finishes and
furnishings, such as drapes, curtains
• NFPA 101: Chapter 10 addresses interior finish requirements
Interior Finish Classes
– Interior finishes are broken down into three classifications:
• Class A Interior Wall and Ceiling Finish (flame spread 025, smoke development 0-450)
• Class B Interior Wall and Ceiling Finish (flame spread
26-75, smoke development 0-450)
• Class C Interior Wall and Ceiling Finish (flame spread
76-200, smoke development 0-450)
• Where the standards require C, A or B can also be used
• Where the standards require B, A can also be used
Interior Finishes
• Interior Wall and Ceiling Finish
• Interior wall and ceiling finish materials
– Less than 1/28” not considered interior finish if they
meet Class A testing requirements
–Fixed or moveable walls and
partitions, paneling, wall pads,
acoustical materials, insulation, etc.
are considered interior finishes.
– Floor finishes
Floor Finish Classes
• Interior floor finishes are characterized by
their critical radiant flux ratings
– Critical Radiant Flux is the level of radiant heat
energy on the floor covering system at the most
distant flame out point
– It provides a basis for estimating one aspect of
flame-spread behavior for floor covering systems
• Class I: critical radiant flux of not less than .45 W/cm2
• Class II: critical radiant flux of not less than .22 W/cm2
but less than .45 W/cm2
Standards for Specific Materials
• Textile Wall and textile ceiling material
• Expanded vinyl wall and expanded vinyl ceiling
materials
• Cellular or Foamed Plastic
• Metal ceiling panels
Contents and Furnishings
• Upholstered furniture
– Resistant to cigarette ignition
– Char length standards (1 ½”)
• Mattresses
– Char length standards (2”)
– Heat release
Industrial Occupancy
– Interior Finishes in industrial occupancies can be
Class A, B, or C
– In exit enclosures, interior finishes shall be Class A
or Class B
– Floor finishes in exit enclosures including stair
treads and risers shall be not less than Class II.
Protecting Openings
• Depending upon the purpose walls will have
different fire rating requirements
• Load bearing, non-load bearing, interior,
exterior, exit corridor, etc.
• Doors used in these openings must meet
applicable fire ratings
Determining Fire Ratings of Doors
• To determine the appropriate fire rating for a
door you need to know the following:
– The purpose the wall/partition is serving
• Fire barrier
• Exit access corridor
• Horizontal exit
– Fire rating of the component
Smoke Management
• Smoke Management
– Smoke management systems are designed to
modify, dilute, redirect, or otherwise influence the
movement of smoke in a building experiencing a
fire, but not necessarily to control it or limit its
movement.
Smoke Control
– Smoke control systems limit and control the movement of
smoke during a fire
– The most common approach involves pressurizing the
areas on either side of the compartment where the fire is
located and exhausting the fire area.
– This is referred to as dynamic smoke control.
– This method creates a pressure sandwich which tends to
move air (and thus smoke) from the protected areas
towards the fire and move smoke out of the fire area.
– While this does introduce fresh oxygen to the fire area,
most systems are aimed at protecting the occupants and
equipment in the adjacent compartments to allow
evacuation and to allow firemen to gain clear access to the
fire to extinguish it
Dynamic Smoke Control
• Instead of shutting down the ventilation fans
when smoke is detected, dynamic smoke
management systems often require the fans to
continue to run.
• Strategically located dampers open or close to
channel HVAC air into selected areas, creating
high and low pressures as required.
• Areas favored for pressurization are stair towers.
lobbies, hallways, and, in some instances,
elevator shafts.
Static Smoke Control
• Conventional shutdown systems
seek to contain smoke by limiting air
movement.
• Once smoke is detected, ventilating
fans shut down, and low leakage
dampers throughout the system
close to inhibit smoke passage.
Smoke Curtains and Fire Curtains
• Smoke curtains prevent the movement of smoke
and heat from one area to another in a fire by
channeling or containing the smoke and heat.
• Fire curtains are vertical fire barriers that
separate and protect escape routes.
• Automatic curtains are comprised of fire resistant
fabric fixed to a steel roller which is driven by an
internal electric motor.