smoke alarm response and tenability in residential buildings€¦ · [email protected] ...

© 2011 Underwriters Laboratories Inc.

Smoke Alarm Response and Tenability in Residential

Buildings

VISION 20/20 March 27, 2014

Towson, MD

Tom Fabian Corporate Research

UL LLC

Copyright© 2008-2011 Underwriters Laboratories Inc. All rights reserved. No portion of this material may be reprinted in any form without the express written permission of Underwriters Laboratories Inc. or as otherwise provided in writing.

2010 DHS AFG Project

Increase firefighter knowledge and in turn safety by providing credible scientific information developed from full-scale fire testing in realistic single family homes.

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Copyright© 2012 UL LLC. All rights reserved. No portion of this material may be reprinted in any form without the express written permission of UL LLC or as otherwise provided in writing.

Room Furnishings

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Instrumentation

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• Smoke alarms • Smoke concentration • Temperature • CO & CO2 concentration


Instrumentation (Post-fire)

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Fire scenarios

Scenario Structure Origin

Nuisance alarm – toaster 1 & 2 story Kitchen

Cooking fire – toaster 1 & 2 story Kitchen

Cooking fire – bacon 1 & 2 story Kitchen

Cooking fire – cabinet spread 1 & 2 story Kitchen

Smoldering upholstered furniture (central location) 1 & 2 story Living room, Family room

Smoldering upholstered furniture (remote location) 2 story Den

Flaming upholstered furniture (central location) 1 & 2 story Living room, Family room

Flaming upholstered furniture (remote location) 2 story Den

Smoldering bedding 1 & 2 story Bedroom

Flaming bedding 1 & 2 story Bedroom

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Cooking Scenarios BREAD AND BACON

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Alarm Response to Burning Bread 1 STORY VS. 2 STORY

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Alarm Response to Cooking Bacon 1 STORY VS. 2 STORY

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Last alarm activated >500 s before transition


Cooking Fire Findings

•  Ion-based alarms responded sooner than photo-based alarms

•  Detection technology appears to be more impactful than increasing alarm distance from 11 to 19 ft away from cooking appliances

•  Even the slowest alarm to activate was well before flaming transition (> 500 s)

Ø  Bacon cooking smells really good; burning bacon smells awful!

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Flaming Fire

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obscuration

alarms

ignition

ignition

ignition

EXIT IR camera


Flaming Fire

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P-I alarm activation


Flaming Fire

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I alarm activation (P-I + 5 s)


Flaming Fire

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I-CO alarm activation (P-I + 10 s)


Flaming Fire

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Adv I alarm activation (P-I + 75 s)


Flaming Fire

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P, P-CO alarm activation (P-I + 138 s)


Flaming Fire

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0.25 OD/m @ 5 ft (P-I + 175 s)


Flaming Fire

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120 °C @ 5 ft (P-I + 360 s)


Flaming Fire

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Termination


Flaming Chair Fire

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Egress threat: Smoke Temp Gases


Smoldering Fire

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obscuration

alarms

heat

heat

heat

EXIT

EXIT


Smoldering Fire

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Smoldering Fire

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Smoke stratification


Smoldering Fire

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P-CO alarm activation


Smoldering Fire

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P-I alarm (P-CO + 6 s)


Smoldering Fire

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P alarm (P-CO + 327 s)


Smoldering Fire

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Forced transition


Smoldering Fire

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I-CO alarm (transition + 55 s)


Smoldering Fire

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I alarm (transition + 64 s)


Smoldering Fire

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Adv I alarm (transition + 84 s)


Smoldering Sofa Fire

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P-C

O a

ctiv

ates

Forc

ed T

rans

ition

Egress threat: Gases Smoke & Temp


Smoke Alarm Findings

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Hazardous conditions are reached sooner and more prevalent in flaming fire scenarios than smoldering fire scenarios Alarm activation was slower in larger houses, particularly for remote fires

Closing bedroom doors retarded alarm activation by: •  75-150 seconds for fires in adjacent areas •  >600 seconds for fires in remote areas

Newest codes (multiple interconnected alarms) provide significantly earlier warning (12 vs. 224 seconds)

Interconnected alarms don’t have these notification delays


Smoke Alarm Findings

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Ion alarms activated earlier than photo alarms in flaming fires: •  ~ 65 seconds for contemporary furniture •  220 seconds for cellulose (legacy) furniture •  190 seconds for remote rooms

Photo alarms activated earlier than ion alarms in smoldering fires: •  ~ 44 minutes in room of origin •  Tended to operate earlier in remote rooms

Unintelligent alarms pairing smoke detection with CO performed similarly to respective conventional alarms

in room of origin

Time lines for escape are seconds to minutes

Time lines for escape are tens of minutes

If a tree falls in the woods…


Sound Level Measurement

Maximum RMS value, fast response, A-weighting

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Sound Levels in 1 Story Test Structure

I 64 56

P 64 49

C 61 52

Welcome

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I 71 45

P 70 47

C 71 43

I 68 56

P 63 55

C 69 56

Ambient level is 40-42 dBA

Open door Closed door

I 87 P 81 C 90

I 87 94 P 81 89 C 90 96

Alarm clock 62 TV @ 10 ft 73 Stereo 80


Sound Levels in 2 Story Test Structure

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Welcome

I 62 P 62 C 65

I 75 P 68 C 75

I 89 P 83 C 87 I 77

P 74 C 76

I 53 P 56 C 57

I 60 48 P 59 54 C 55 49

I 60 42 P 56 43 C 61 44

Open door Closed door

Alarm clock 62 TV @ 10 ft 73 Stereo 80

Ambient level is 40-42 dBA


Overall Conclusions

1. Ion alarms respond faster to flaming fires; Photo alarms to smoldering fires 2. In general current smoke alarm technologies provide critical time to escape IF:

•  Multiple alarms •  Alarms are located per NFPA 72 •  Alarms are interconnected

3. Nuisance alarm activations due to cooking can be reduced by:

•  Moving alarms further away from the cooking appliances •  Using Photo alarm

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and they are maintained

[email protected]

http://www.ul.com/fireresearch

Questions and Discussion

The Near and Not-So Distant Future…


1) UL 217/268 STP New Fire Test Task Group

GOAL: Increase available egress time for non-specific fires by expanding alarm responsiveness to other smoke signatures by expanding the range of smoke colors and particle sizes currently represented by UL 217 test materials.

⇒ Develop new flaming and smoldering polyurethane (PU) foam fire tests to compliment existing UL 217 and 268 tests.

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1) UL 217/268 STP New Fire Test Task Group WHY POLYURETHANE FOAM?

From the UL-FPRF Smoke Characterization Project:

•  Fast ignition

•  Generate greater heat and smoke release rates than natural materials

•  Generate smaller sized particles than most UL 217 test materials

•  Produce accumulated smoke comprised of smaller particles than for the UL 217 test materials

•  Produce darker color smoke than UL 217 newspaper or wood

Prevalence in residences (mattresses, upholstered furniture, etc.)

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1) UL 217/268 STP New Fire Test Task Group UL 217/268 & FOAM SMOKE SIGNATURES

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Flammable Liquid

Flaming Wood

Flaming Paper

Smoldering Foam

Smoldering Wood

Flaming Foam

Copyright© 2008-2011 UL LLC. All rights reserved. No portion of this material may be reprinted in any form without the express written permission of UL LLC or as otherwise provided in writing.

1) UL 217/268 STP New Fire Test Task Group NEW UL 217/268 FOAM FIRE TESTS

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Flaming test Smoldering test

⇒ Small, dark particles ⇒ Large, light particles


2) Multi-Sensor Approach to Detecting Fire

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Light

Smoke

Gases H2O, CO2, CO, Hydrocarbons,

HCN, HCl

Heat


2) Multi-Sensor Approach to Detecting Fire HOW MULTI-SENSOR/CRITERIA WOULD OPERATE

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Modified image from Oak Ridge National Laboratory

Smoke

Gases

Heat

(where Xʹ′ = rate of change)

Intelligent Algorithm

T Tʹ′ Ion

Ionʹ′ PE

PEʹ′ CO

COʹ′ CO2

HCsʹ′ HCs

CO2ʹ′


2) Multi-Sensor Approach to Detecting Fire MULTI-SENSOR SIGNALS

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UL-FPRF Smoke Characterization Project

Plots courtesy of ORNL


Future Trends

1.  Yesterday’s conventional alarms will be challenged by the new tests.

2.  Smoke detectors and alarms will (are) become more sophisticated using multiple sensors, technologies, and intelligent algorithms.

•  Multiple wavelengths of light (IR, green, blue)

•  Multiple angle scattering

•  Smoke + gas + heat

3.  Interconnected is here to stay.

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[email protected]

http://www.ul.com/fireresearch

Questions and Discussion

smoke alarm response and tenability in residential buildings€¦ · [email protected] ...

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