THERMAL TESTING: WHAT YOU NEED TO KNOW

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Transcript THERMAL TESTING: WHAT YOU NEED TO KNOW

FLAME RESISTANT CLOTHING FOR PROTECTION AGAINST FLASH FIRE HAZARDS

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WHY FLAME RESISTANT PROTECTIVE CLOTHING?

IN NORTH AMERICA, THERE ARE MORE THAN 7,000 CLOTHING-RELATED WORKPLACE INJURIES EACH YEAR DUE TO FIRE.

THE MOST SEVERE BURNS ARE CAUSED BY IGNITED CLOTHING, NOT BY THE ORIGINAL FLASH FIRE.

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WHY FLAME RESISTANT PROTECTIVE CLOTHING? (Continued)

CLOTHED AREAS CAN BE BURNED MORE SEVERELY THAN EXPOSED SKIN.

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CLOTHED AREAS CAN BE BURNED MORE SEVERELY

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THE IMPORTANCE OF THERMAL PROTECTIVE APPAREL Thermal Protective Apparel – Maintains a Barrier to Isolate the Wearer From the Thermal Exposure – Traps Air Between the Wearer and the Barrier to Provide Insulation From the Exposure – Reduces Burn Injury and Provides Escape Time – Does Not Burn, Melt or Drip 5

THE IMPORTANCE OF THERMAL PROTECTIVE APPAREL (Continued)

Survival, Extent of Injury, Recovery, and Quality of Life Depend on Protection Provided by Thermal Protective Apparel 6

DATE OF ACCIDENT TOTAL PAID RESERVE AMOUNT 07/29/93 Medical $ 618,301.81

$ 978,928.00

= 562,677.78 250,000.00

Indemnity = 52,182.14 721,437.00

Vocational = 2,510.36 7,438.00

Expenses = 931.53 0.00

07/12/94 Medical $ 217,128.98 $ 124,999.00

= 184,572.12 124,999.00

Indemnity = 30,143.43 19,226.00

Vocational = 2,393.43 7,606.00

Expenses = 20.00 0.00

06/01/95 Medical $ 40,682.21

Indemnity = 6,035.28

$ 4,564.00

= 32,707.38 4,564.00

0.00

Vocational = 1,903.55 0.00

06/01/95 Medical $ 12,309.92

$ 0.00

= 9,213.25 0.00

Indemnity = 1,890.57 0.00

Vocational = 1,195.40 0.00

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FLAME RESISTANT CLOTHING

Flame Resistant Clothing Will Not Ignite and Continue to Burn From Exposure to Flame.

Examples of Flame Resistant Clothing Products: – Products With Flame Retardants »FR Rayon Blends with Nomex® »Firewear® Modacrylic Cotton Blend »Flame Retardant Treated Cotton 8

FLAME RESISTANT CLOTHING (Continued) – Inherently Flame Resistant Products »Kevlar®/PBI Blends »Nomex®/Kevlar® Blends »Nomex® IIIA 9

BURN INJURY PRINCIPLES

BURN DEPTH IS A MEASURE OF SEVERITY – FIRST-DEGREE: SKIN BECOMES RED, NO BLISTER – SECOND-DEGREE: SKIN BLISTERS, EPIDERMIS MUST REGENERATE (100 MICRON DEPTH) 10

BURN INJURY PRINCIPLES (Continued) – THIRD-DEGREE: FULL THICKNESS DESTROYED, SKIN CANNOT REGENERATE, SCAR TISSUE FORMS (1,000-MICRON DEPTH)

EXPOSURE TO AN ELECTRIC ARC OR FLAME CAN RAPIDLY EXCEED HUMAN TISSUE TOLERANCE AND CAUSE SECOND- OR THIRD-DEGREE BURNS 11

CHANCES OF SURVIVAL FROM BURN INJURY 100 80 60 40 20 0

20-29 30-39 40-49 50-59

Age Range, Years Source: American Burn Association (1991-1993 Study) 12 25% Body Burn 50% Body Burn 75% Body Burn

CHARACTERISTICS OF A GOOD FLASHFIRE TEST

Realistic Exposure Conditions That Simulate Real Life Hazards – Exposures Like Real Flash Fires – Fabric Sample Configuration Like Clothing on a Human Body 13

CHARACTERISTICS OF A GOOD FLASHFIRE TEST (Continued)

Meaningful Results – Clear Direction on Clothing Choices – Clear Differences Between Materials

Reproducible – Test to Test, Lab to Lab

Flash Fire Manikin Test Provides an Excellent Match for These Characteristics 14

EXPOSURE ENERGY

Exposure Energy is Expressed in Cal/Cm 2

Copper Calorimeters Are Used to Measure Exposure Energy

1 Cal/Cm Second 2 Is Equivalent to the Energy Produced by a Cigarette Lighter in One

An Exposure Energy of One or Two Cal/Cm Skin 2 Will Cause a Second-Degree Burn on Human 15

EXPOSURE ENERGY (Continued)

Heat Flux Is the “Flow Rate” of Energy Onto a Surface

Exposure Energy = Heat Flux X Exposure Time

Typical Values for Industrial Flash Fire: – Heat Flux – Exposure Times 1-4 Cal/Cm 2 -Sec.

1-5 Sec.

– Exposure Energies1-20 Cal/Cm 2 16

EXAMPLES OF ESTIMATED TOTAL INCIDENT ENERGY OF VARIOUS HAZARDS

Exposure Description Oil Well - Flash Fire Brush Fire Backdraft from Gas Line Leak Solvent Vapor - Flash-Over/Paint Shop Apartment Building Fire 13.2 kV System Electric Arc Underground Vault 4.8 kV System Electric Phase to Ground Arc Garment of Nomex® Aramid Fiber Estimated Total Exposure Energy, cal/cm2 Coveralls Shirt 4 12 Turnout Coat Turnout Coat Turnout Coat 7 16 19

EXAMPLES OF EXPOSURE ENERGY.

HAZARD WAS DETERMINED FROM DAMAGED GARMENTS IN THESE INCIDENTS.

Coveralls 35 Shirt

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THERMO

-

MAN

®

Nomex® Coverall

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MANIKIN TESTING

Realistic Flash Fire Exposure Conditions – Controllable Heat Flux and Exposure Time – Results Reflect Actual Industrial Exposures

Full Size Instrumented Manikin With 122 Thermal Sensors Measures Heat Transfer Through Garment

Amount, Degree, and Location of 19 Predicted Burn Injury Calculated From

MANIKIN TESTING (Continued)

Bottom Line: Provides a Prediction of Burn Injury for Specific Garment Over a Full Range of Flash Fires 20

THERMO-MAN

®

Nomex® Coverall Initial Torch Ignition

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THERMO-MAN Nomex® Coverall

®

Full Flash Fire Exposure

2

2 cal/cm sec

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THERMO-MAN Nomex® Coverall

®

After Torches Extinguish

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THERMO-MAN® EVALUATION Conditions 5X Home Launderings 100% Cotton Underwear Heat Flux of 2 cal/cm 2 sec Average of 3 Data Points 100 90 80 70 60 50 40 30 20 10 0 2.5

3.0

3.5

4.0

Exposure Time, Sec.

24 4.5

5.0

THERMO-MAN ® Flammable Coverall Full Flash Fire Exposure

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THERMO-MAN

®

Flammable Coverall Continues Burning After Torches Extinguish

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THERMO-MAN® SIMULATED FLASH FIRE EVALUATION

100% Untreated Cotton (5.7 oz/yd 2 )

100 Conditions 90 5X Home Launderings 80 70 100% Cotton Underwear 60 50 Heat Flux of 2 cal/cm 2 sec 40 30 Average of 3 Data Points 20 Data Acquisition Time 60 sec.

10 0 2.5

3.0

Exposure Time, Sec.

3.5

4.0

4.5

27 5.0

Conditions 5X Home Launderings 100% Cotton Underwear Heat Flux of 2 cal/cm 2 sec Average of 3 Data Points THERMO-MAN® EVALUATION 100 90 80 70 60 50 40 30 20 10 0 2.5

100% Untreated Cotton (5.7 oz/yd 2 ) Firewear® (6.1 oz/yd 2 ) Firewear® (10.2 oz/yd 2 ) Nomex® IIIA (6.1 oz/yd 2 ) 4.5

5.0

3.0

28 3.5

4.0

Exposure Time, Sec.

Conditions 5X Home Launderings 100% Cotton Underwear Heat Flux of 2 cal/cm 2 sec Average of 3 Data Points THERMO-MAN® EVALUATION 100 90 80 70 60 50 40 30 20 10 0 2.5

100% Untreated Cotton (5.7 oz/yd 2 ) “Indura” FRT Cotton (10.2 oz/ yd 2 ) “ Indura” FRT Cotton (6.1 oz/ yd 2 )

3.0

Exposure Time, Sec.

3.5

4.0

29 4.5

5.0

THERMO-MAN® EVALUATION Conditions 5X Home Launderings 100% Cotton Underwear Heat Flux of 2 cal/cm 2 sec Average of 3 Data Points 100 90 80 70 60 50 40 30 20 10 0 2.5

3.0

100% Untreated Cotton (5.7 oz/yd 2 )

Exposure Time, Sec.

3.5

4.0

4.5

30 5.0

ESTIMATED THERMO-MAN® PREDICTED BURN INJURY FOR STATION UNIFORMS/TURNOUT SYSTEMS 100 80 60 40 20 0 0 1 2 3 4 5 6 EXPOSURE TIME, SECONDS 31 7 8 9 10

FLAME-RESISTANT CLOTHING SYSTEM COMMON SENSE GUIDELINES

Proper Wearing Procedures – Protective Clothing Selection Must Be Based on the Probable Worst Case Exposure for a Task.

– Flame-Resistant Workwear Should Provide a Good Functional Fit for Protection and Comfort. Loose Fitting Clothing Provides Additional Thermal Protection Due to Increased Air Spaces.

FLAME-RESISTANT CLOTHING SYSTEM COMMON SENSE GUIDELINES (Continued) – Sleeves, Shirt, and Outerwear Should Be Fully Buttoned.

– Appropriate Protective Neck, Face, Head, Hand, and Foot Coverings Should Be Worn.

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FLAME-RESISTANT CLOTHING SYSTEM COMMON SENSE GUIDELINES (Continued)

Outerwear Must be Flame Resistant – Flammable Outerwear Can Ignite and Continue to Burn Essentially Eliminating the Protection of Flame Resistant Clothing Worn Underneath 34

FLAME-RESISTANT CLOTHING SYSTEM COMMON SENSE GUIDELINES (Continued) – An Ignited Flammable Outer Garment Creates a Heat Source Close to the Skin, e.g., A Nylon Wind Breaker Worn Over an Flame Resistant Coverall. Although the Flame-Resistant Coverall Will Not Burn, the Wearer Can Be Burned by the Additional Heat Transfer From the Ignition of the Flammable Outerlayer.

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FLAME-RESISTANT CLOTHING SYSTEM COMMON SENSE GUIDELINES (Continued)

Under Garments (Underwear Worn Against the Skin) Should be Non-Melting – Non-Melting Undergarments, I.E., Cotton, Wool, Silk, Rayon, Can Be Worn to Increase Thermal Insulation and Protection.

– Meltable Undergarments Can Increase Burn Injury Severity Due to Melt Adhesion to the Skin.

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