7.1 smoke detector performance - ul · 2014-10-26 · • nfpa 72 chapter 11 task group activities...

February 20, 2009

7.1 Smoke Detector Performance

Paul E. Patty, P.E.Senior Research EngineerNorthbrookX [email protected]

February 20, 2009p/2

Smoke Detector Performance

• Smoke Characterization Project– Quality of smoke– Material characteristics– Smoke movement– Photo/Ion response

• STP Activities– Improving response– Nuisance issues

• NFPA 72 Chapter 11 Task Group Activities– Tenability issues

• Media Coverage Photoelectric/Ionization Alarms– Is there a hazard?

• Recommendations


Smoke Detector Performance Smoke Characterization Project

• Quality of smoke– Color

• black, grey, yellow, white– Particle size

• .01-10 microns– Velocity

• > 32ft/min.– Temperature

• <150 degrees F– Build-up rate

• obscuration %/ft/min.– Gases of combustion


Smoke Characterization Project

• Material characteristics– Develop smoke characterization analytical test protocol using flaming and

non-flaming modes of combustion.– Develop smoke particle size distribution data and smoke profiles in the UL

smoke detector room for materials found in residential settings for both flaming and non-flaming modes of combustion.

• Survey Materials – Survey materials and products in contemporary residential settings– Selection of materials for the research investigation based on:

• Presence in residential settings

• Chemistry

• UL 217 specifications


Smoke Characterization Project Sampling Method

N2dilution

FTIREvery 15 s

Calorimeter

Smoke ParticleEvery 67 s


Smoke Characterization Project Smoke Particle Analyzer Data

PET Carpet

11 17 26 40 6310

216

929

736

044

5

575

900 0

48115

182249

316383

450517

584

0.0E+00

2.6E+05

5.1E+05

7.7E+05

1.0E+06

1.3E+06

Particle density (1/cc)

Particle Size (nm)

Time (s)


Smoke Characterization Project Key Findings - Gas Analysis

• Smoke Gas Effluent Composition - Gas effluent analysis showed the dominant gas components were water vapor, carbon dioxide and carbon monoxide.

Water CO2 COSO2 NO2 MethaneAmmonia Phenol SiF4Formaldehyde HCN PropaneHCl HF EthyleneAcrylonitrile Styrene


Smoke Characterization Project Key Findings - Influence of Material Chemistry

0

100

200

300

400

500

600

700

800

Cookin

g oil

Heptan

e

Heptan

e/ Tolu

ene m

ixDou

glas f

irNew

spap

erPon

d. pin

eHDPEBrea

d

Mattres

s com

posit

e

Mattres

s PU fo

amCott

on ba

tting

Polyes

ter pi

llow st

uffing

Cotton

/Poly

ester

blen

d fab

ricRay

on fa

bric

Nylon c

arpet

PET carpe

t

Polyiso

cyan

urate

foam

PVC wire

Pea

k H

RR

(kW

/m²)

UL 217 materials

Flaming Mode


Smoke Characterization Project Key Findings - Mode of Combustion

0.00

0.05

0.10

0.15

0.20

0.25

0.30

Cookin

g oil

Bread

Newsp

aper

Dougla

s fir

Ponde

rosa p

ineCott

on ba

tting

Cotton

/Poly

ester

blen

d (fab

ric)

Rayon

(fabri

c)

HDPENylo

n carp

etPoly

ester

carpe

tPoly

ester

fillin

g

PU foam

Polyiso

cyan

uarat

e foa

m

PVC M

ean

Par

ticle

Dia

met

er (m

icro

n)

FlamingNon-Flaming

UL 217 materials


Smoke Characterization Project Key Findings - Mode of Combustion

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Cookin

g oil

Bread

Newsp

aper

Dougla

s fir

Ponde

rosa p

ineCott

on ba

tting

Cotton

/Poly

ester

blen

d (fab

ric)

Rayon

(fabri

c)

HDPENylo

n carp

etPoly

ester

carpe

tPoly

ester

fillin

g

PU foam

Polyiso

cyan

uarat

e foa

m

PVC S

peci

fic E

xtin

ctio

n A

rea

(m²/g

)

FlamingNon-Flaming

UL 217 materials


Smoke Characterization Project Key Findings – Particle size

Mean Diameter at:Flaming Tests0.5 %/ft 10 %/ft

Douglas fir 0.13 0.17Newspaper 0.17 0.18Heptane/Toluene 0.19 0.30Coffee maker 0.17 0.18PU foam 0.08 NAPU foam in Cotton/Poly 0.09 NANylon carpet 0.10 NA


Smoke Detector Performance Smoke movement

• Smoke Stratification - Non-flaming fires result in changes in the smoke build up over time, such that stratification of smoke below the ceiling occurs. This time-dependent phenomenon results in less obscuration at the ceiling than below the ceiling. This caused both detection technologies to drift out of alarm.


Smoke movement Key Findings - Fire Test Room

• BeforeBefore

• After


Smoke movement

0

2

4

6

8

10

12

0 1000 2000 3000 4000 5000 6000 7000

Time (sec)

OB

S (%

/ft)

4 in below ceiling

24 in. below ceiling


60 in below ceiling

PU foam in Poly


Smoke movement

0

2

4

6

8

10

12

0 1000 2000 3000 4000 5000 6000 7000

Time (sec)

OB

S (%

/ft)

4 in below ceiling




PU foam in Cotton


Smoke Detector Performance (Photo/Ion Response Fire Test Room MIC 1)

0

10

20

30

40

50

60

70

80

90

100

0.0E+00 2.0E+05 4.0E+05 6.0E+05 8.0E+05 1.0E+06

Σ(n idi)

MIC

Sig

nal C

han

ge (

pA)

Bread

Bread

Bread

Nylon Carpet

PolyisocyanurateFoamPolystyrene

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

PU Foam

PU Foam

PU Foam

PU + cotton

PU + cotton

PU + poly

PU + Poly

Non-Flaming Tests


Photo/Ion Response Fire Test Room MIC 2

0

10

20

30

40

50

60

70

80

90

100

0.0E+00 2.0E+05 4.0E+05 6.0E+05 8.0E+05 1.0E+06

Σ(nid i)

MIC

Sig

nal C

han

ge (

pA) Coffee Maker

Coffee Maker

Nylon carpet

Nylon carpet

Nylon carpet

PU Foam

PU Foam + cotton/poly




Flaming Tests


Photo/Ion Response Fire Test Room Analog Ion 1

0

10

20

30

40

50

60

70

0.0E+00 2.0E+05 4.0E+05 6.0E+05 8.0E+05 1.0E+06

Σ(nidi)

An

alo

g Io

n S

igna

l Ch

ange

Bread

Bread

Bread

Nylon Carpet

Isocyanuarate Foam

Polystyrene

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

PU Foam

PU Foam

PU Foam

PU Foam

PU Foam + cotton

PU Foam + poly

PU Foam + polyNon-Flaming Tests


Photo/Ion Response Fire Test Room Analog Ion 2

0

10

20

30

40

50

60

70

0.0E+00 2.0E+05 4.0E+05 6.0E+05 8.0E+05

Σ (nidi)

Ana

log

Ion

Sig

nal C

han

ge

Coffee Maker

Coffee Maker

Douglas Fir

Douglas Fir

Douglas Fir

Heptane/Toluene

Heptane/Toluene

Heptane/Toluene

Heptane/Toluene

Newspaper

Newspaper

Newspaper

Nylon Carpet

Nylon Carpet

Nylon Carpet

PU Foam





Flaming Tests


Photo/Ion Response Fire Test Room Beam 1

0

5

10

15

20

25

30

35

40

0.0E+00 2.0E+04 4.0E+04 6.0E+04 8.0E+04 1.0E+05 1.2E+05

Σ (n idi3)

OB

S (

%/ft

)

Bread

Bread

Bread

Nylon Carpet

PolyisocyanurateFoamPolystyrene

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

PU Foam

PU Foam

PU Foam

PU Foam + cotton

PU Foam + cotton

PU Foam + Poly

PU Foam + Poly

Non-Flaming Tests

Alarm Trigger Range


Photo/Ion Response Fire Test Room Beam 2

0

5

10

15

20

25

30

35

40

0.0E+00 2.0E+04 4.0E+04 6.0E+04 8.0E+04 1.0E+05 1.2E+05

Σ (n idi3)

OB

S (

%/ft

)

Coffee Maker

Coffee Maker

Douglas Fir

Douglas Fir

Douglas Fir

Douglas Fir

Heptane/Toluene

Heptane/Toulene

Heptane/Toluene

Newspaper

Newspaper

Nylon Carpet

Nylon Carpet

Nylon Carpet

PU Foam

PU foam + cotton/poly



Flaming Tests


Photo/Ion Response Fire Test Room Analog Beam 1

0

10

20

30

40

50

60

0.0E+00 5.0E+04 1.0E+05 1.5E+05 2.0E+05 2.5E+05

Σ(nidi2)

An

alo

g P

hoto

Sig

nal C

han

ge

Bread

Bread

Bread

Nylon Carpet

Isocyanurate Foam

Polystyrene Foam

Ponderosa Pine

Ponderosa Pine

Ponderosa Pine

PU Foam

PU Foam

PU Foam

PU Foam + cotton

PU Foam + poly

PU foam + poly

Non-Flaming Tests


Photo/Ion Response Fire Test Room Analog Beam 2

0

10

20

30

40

50

60

0.0E+00 5.0E+04 1.0E+05 1.5E +05 2.0E+05 2.5E+05

Σ (n idi2)

Ana

log

Pho

to S

igna

l Cha

nge

Coffee MakerCoffee MakerDouglas FirDouglas FirDouglas FirHeptane/TolueneHeptane/TouleneHeptane/TolueneNewspaperNewspaperNewspaperNylon CarpetNylon CarpetNylon CarpetPU FoamPU Foam + cotton/polyPU Foam + cotton/polyPU Foam + cotton/poly

Flaming Tests


Particle Size Influence on Sensing Technology

d, Particle Size

Rel

ativ

e Si

gnal

Sen

sitiv

ity

Obscuration ~ d3

Scattering ~ d2

Ion ~ d

⇒ Physics of ionization technology is linearly responsive to particle size.

⇒ Physics of light-based technologies are more responsive to larger particles than smaller particles.


STP Activities

• Improve alarm/detector response‐ New polyurethane smoldering, and flaming tests‐ Adjust obscuration base‐ Adjust time base

• Nuisance alarm issues‐ Spike values‐ Spike duration‐ Gases of combustion‐ Marking


Development: Flaming & smoldering polyurethane tests

• Develop new flaming and smoldering polyurethane (PU) foamfire tests to compliment existing UL 217 and 268 tests.

⇒ Increase available egress time for non-specific fires by expanding alarm responsiveness to other smoke signatures.

• Rationale– Flaming PU foam generates smaller smoke particles than the

current fire tests.– Synthetic materials generate greater heat and smoke release rates

than natural materials.– Prevalence of PU foam in residential settings (mattresses,

upholstered furniture, etc.).


“Standard” Foams Currently Used

Product Test MethodFoam Test Material Description

Smoke detectors

EN 54-7,ISO 12239

“Soft polyurethane foam”- No fire retardant- Density: c. 20 kg/m3

ASTM E 1353,CPSC 1634

SPUF: Polyurethane foam- No inorganic fillers or FR- Density: 28.8 ±1.6 kg/m3 (1.8 ±0.1 lb/ft3)

CA TB117+,CPSC 1634

SFRPUF: Flame-retardant polyurethane foam- Density: 22.4 ±1.6 kg/m3 (1.4 ±0.1 lb/ft3)

UFACPolyurethane foam- No inorganic fillers or FR- Density: 24.0 ± 1.6 kg/m³ (1.5 ± 0.1 lb/ft³)

Residential sprinklers UL 1626

Polypropylene oxide polyol, polyether foam- Density: 27.2 - 30.4 kg/m3 (1.70 - 1.90 lb/ft3)- PHRR at 30 kW/m2: 230 ±50 kW/m2

- HOC at 30 kW/m2: 22 ±3 kJ/g

Upholstered furniture


Scenario Development

• Task Objectives:– Investigate influence of scenario variables on combustion

products.– Develop smoke particle size and gas effluent data on the

scenarios.

Test Parameters:Variables Output

Foam densitySample size & shape Smoke build-up rate

Heating method


Flaming Fire Scenarios

• Goal:– Flaming foam test that achieves obscuration levels similar to the

UL 217 flaming tests in a comparable time frame.

• Potential Scenarios:– EN 54-7 TF 4 flaming foam test– Variations in foam density, sample size & shape, ignition point


Smoldering Fire Scenarios

• Goal:– Smoldering foam test that:

• Achieves 10 %/ft obscuration at 45 min.• Achieves 12-15 %/ft obscuration by 60 min.• Avoids settling/stratification (test < 75 min.).

• Potential Scenarios:– Radiant panel: Heat from sample top surface– Hot plate: Heat from sample bottom surface– Cigarette ignition: Heat from sample top surface but

covered– Hot wire: Heat from sample center


Flaming Fire Scenarios

2 step burning process:• Flame front• Molten sample

Variables:• Foam density• Sample size & shape• Ignition point

Completed:• 26 Calorimeter tests• 22 Fire Room tests

⇒ Flame-out ranged from260 to 2129 s

⇒ 10 %/ft Obs reached in85 to 1540s & never


Polyurethane Flaming Test Sample


NFPA 72 Chapter 11 Task Group Activities

• Test method variability– Tenability issues

• 3 foot visibility• 20 foot visibility


Media Coverage

• Photoelectric/Ionization Alarms– Test demonstrations in question– Is there a hazard?– Earliest possible warning– New vs. existing construction

• No scientific study shows superiority of one technology over another when installed per NFPA 72.

• Not measuring the quality of smoke can lead to misleading conclusions.

• The movement of smoke in a building is a complex issue


Recommendations

• The responsiveness of smoke alarms depend upon a number of factors including the type of fire (smoldering, flaming), the chemistry of materials involved in the fire, and the color of the resulting smoke. Both ionization and photoelectric type smoke alarms provide adequate response to these factors but their sensitivity to them varies. Therefore, several fire safety organizations recommend a consumer utilize both ionization and photoelectric technology, or another technology with similar performance characteristics, in their home smoke alarm systems to permit the longest potential escape times for nonspecific fire situations.


Recommendations

• Installing Listing products as follows:1. as described by the manufactures instructions2. as required by the minimum requirements of NFPA 72

• Reduces ones risk to lose of life, or injury resulting from a nonspecific fire.

• Deviating from these two simple steps can cause you to lose the benefit of early warning from your fire alarm system.


7.1 Smoke Detector Performance

QUESTIONS

Paul E. Patty, x42752

7.1 smoke detector performance - ul · 2014-10-26 · • nfpa 72 chapter 11 task group activities...

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