Assessing the Effect of Barrier Fabrics on the Heat 

Release Rate of Residential Upholstered Furniture

Andre Thompson, Ickchan Kim, and Mauro Zammarano

Fire Research Division, Engineering Laboratory, National Institute of Standards and Technology, USA 

Introduction

Experiment and Results

• In the U.S., residential upholstered furniture (RUF) fires are the

single largest cause of civilian deaths in home fires (about 25%) [1].

• The fire safety community has developed test methods and mitigation

strategies to assess whether certain technologies can reduce the fire

hazard of RUF by suppressing smoldering and flaming combustion.

• Recent analysis of fire losses indicates that a majority of the RUF fire

deaths and other losses occur during flaming, rather than smoldering

combustion, regardless of the ignition source type [2].

• We conducted a series of full-scale tests focused on quantifying the

ability of 6 different commercially available barrier fabrics (BFs)

(compliant with California State Assembly Bill No. 2998 [3]) to

reduce the heat release rate (HRR) and delay the fire growth of fullscale chair mock-ups.

References

[1] Hall, J.R., Estimating Fires When a Product is the Primary Fuel But Not the First Fuel, With an Application to Upholstered Furniture, 

National Fire Protection Association, (2014).

[2] Gann, Richard G. Reducing the Fire Hazard of Residential Upholstered Furniture (RUF), CPSC Meeting on Furniture Flammability, (2018).

[3] A.B. 2998, Bloom. Consumer products: flame retardant materials, (Cal. 2018).

[4] California Dept of Consumer Affairs. Bureau of Home Furnishings and Thermal Insulation. Flammability Test Procedure for Seating 

Furniture for Use in Public Occupancies. [Technical Bulletin 133] (1991). Retrieved from: https://bhgs.dca.ca.gov/industry/tb133.pdf 

Chair Mock-ups: Chair Construction

• All 6 fire barriers tested (compliant with [3]) delayed the fire growth and significantly 

increased available time for safe egress and for firefighter response.

• B1 and B6 showed the longest time to peak (~22 mins)

• Barrier failure due to mass transfer of liquid pyrolizates percolating through the 

barrier and resulting in abrupt HRR increase and pool fire formation.

Effect of Fire Barriers

Conclusion

0

500

1000

1500

2000

2500

3000

0 5 10 15 20 25 30 35 40

HRR (kW)

Time (min)

B0

B2

B4

B6 B1

B5

B3

Seams 

(Metal Staples) 

Fire Barrier

Foam or Polyester Fibers

Cover Fabric

• 7 chair types Cushion Design

o 1 cover fabric (B0), polypropylene 

o 6 fire barriers (B1-B6)

• Triplicate tests = 21 chairs

• Propane burner by Cal TB 133 [4]

Ignition Source

Bottom of Chair Barrier Failure Mechanism

Effect of Fire Barriers on HRR

0

200

400

600

800

1000

1200

0 5 10 15 20 25 30 35 40

HRR (kW)

Time (min)

TTBI

Time to BI 

Plateau Duration

HRRBI

HRR at Bottom 

Ignition

Data Summary

Barrier Materials

Barrier Barrier Sample Fabric Type Materials

Density

g∙m-2

Air Perm. 

cm3∙s-1∙cm-2

B0 Cover fabric Polypropylene 340 ± 7 3.9 ± 0.3

B1 Nonwoven-bonded 

polyester 

RC**/PSA*(top), 

cotton (bottom) 239 ± 21 22.4 ± 1.4

B2 Woven E glass, no sizing 109 ± 4 9.2 ± 2.2

Note: RC** = Regenerated Cellulose; PSA*= Polysilicic Acid

• Heat Flux 18 kW applied for 80s

• Located 1 inch above the seat

Barrier THR

(MJ)

EHC 

(MJ/kg)

Mass Loss

(%)

PHRR

(kW)

TTP

(min)

TBI 

(min)

TTP-TTBI 

(min)

B0 311 ± 5 24.3 ± 0.4 93 ± 3 2610 ± 154 3.3 ± 0.2 2.2 ± 0.1 1.1 ± 0.1

B1 307 ± 12 22.4 ± 0.3 87 ± 0 888 ± 157 22.2 ± 2.2 20.0 ± 2.3 2.2 ± 0.9

B2 288 ± 8 23.9 ± 0 82 ± 2 2025 ± 329 11.5 ± 1.4 9.9 ± 1.9 1.6 ± 0.5

B3 328 ± 3 23.7 ± 0.2 87 ± 2 1030 ± 341 14.1 ± 0.6 9.7 ± 2.0 4.5 ± 1.4

B4 304 ± 2 24.0 ± 0.2 89 ± 1 1817 ± 222 10.9 ± 1.0 9.2 ± 0.3 1.7 ± 0.8

B5 321 ± 3 23.8 ± 0.2 83 ± 0 1648 ± 133 12.6 ± 0.6 10.5 ± 0.7 2.1 ± 0.1

B6 297 ± 6 22.2 ± 0.3 83 ± 1 991 ± 319 22.7 ± 3.4 20.2 ± 3.3 2.6 ± 0.9

Flux Gauge

Ignition of chair (flame spread) Foam pyrolysis to liquid polyol Liquid percolates through the barrier Bottom Ignition Formation of pool fire Pool fire at PHRR

Fire barriers allow to:

• Increase time to peak 

from 3 mins (B0) 

to 22 mins (B1/B6) 

• Decrease PHRR from 

about 3 MW to 

about 1 MW

No barrier at PHRR Barrier B1 at PHRR

t  3 min t  22 min

Barrier Barrier Sample Fabric Type Materials

Density

g∙m-2

Air Perm. 

cm3∙s-1∙cm-2

B3

Nonwoven, 

5% RC** binder

Oxidized polyacrylonitrile fibers

240 ± 22 7.1 ± 0.5

B4 Woven E glass, no sizing 50 ± 1 31.4 ± 4.6

B5

Woven, core 

spun yarns

Para-amid fiber,

Fiberglass core

278 ± 3 2.7 ± 0.0

B6

Nonwoven,

Needle-punched

RC**/PSA* hybrid

Yarn, glass yarn

275± 4 9.7 ± 0.7