Electrical Arc Flash:

ProtectingProtecting against residual risk - DuPont‘s “4 P“ Approach

Elaina Harvey - Electric Arc End User Specialist - Nomex®

The DuPont Oval, DuPont™, The miracles of science™, Nomex® and ArcMan® are registered trademarks or trademarks of DuPont or its affiliates

Alsico AcademyA plus A

Predict Prevent

ProtectPublishPublish

Results & Training

Re-evaluate

Can we apply further

prevention techniques?

Apply ProtectionMeasures

ResultsPredictSeverity

Residual Risk

START

YES

NO

DuPont’s Methodology for Approaching Arc Risk Hazards

What is an Electric Arc?

PlasmaMolten MetalPressure WavesSound WavesShrapnelHot Air-Rapid ExpansionIntense UV Light and Infra Red RadiationCopper Vapor:Solid to Vapor ExpandsRadiant and Convective Heat 20’000 °C. (Temp on surfaces only a few hundred oC)

1

2

3

47

1

2

3

4

5

6

7

8

56

8

Usually an inadvertent contact between an energised conductor with another conductor or an earthed surface.

Possible causes of electrical arcs:• Accidental contact with energized parts • Contamination (e.g. dust) on insulating

surfaces• Wiring errors• Corrosion of equipment parts and contacts • Improper work procedures Arc flash Incident

Two different ways of testing Protective Clothing & Materials

Determination of the Thermal effects of an Electric Arc on PPE

Determination of theIncident Energy

Simulation of definedscenarios

EN / IEC 61482-1-1

(Open Arc Test)EN / IEC 61482-1-2

(Box Test)

Thermal Resistance:Arc Thermal Performance Value (ATPV) or

Breakopen Threshold Energy (EBT50)

Arc Protection Classes:Class 1 (4kA) Class 2 (7kA)

Pass/Fail

IEC 61482-2 (Draft EN 61482-2)Requirements for Material Performance & Garment Design,

Marking & User Information

(Value is > Prospective Incident Energy identified during risk assessment)

Protect

DuPontTM Arc-Man®

in accordance to

Jacket

Arc Rating* Body Protection

ATPV > 4 cal/cm2

Box Test Class 1

ATPV > 8 cal/cm2

Box Test Class 1

ATPV > 12 cal/cm2

Box Test Class 1

ATPV > 25 cal/cm2

Box Test Class 2

ATPV > 40 cal/cm2

Box Test Class 2

Ensuring Fit-for Purpose Garments for Your Situation

Long Sleeved Business Shirt

Long Sleeved Polo Shirt

Trousers Coverall Coat

OPTI

ONAL

OPTI

ONAL

Weather Jacket & Trouser

* In Europe there are not ATPV category classes like there is in the USA according to NFPA 70

• Using Nomex® provides lightweight comfortable layering to the relevant level of protection

• Ensures worker is not restricted from cumbersome clothing

4 to > 40 cal/cm2 / Class 1 & Class 2 systems available

Examples In DuPont’s Thermal Industrial Guide

7

Wish To Find Out More Information?

• www.arcguide.dupont.com

• www.nomex.co.uk/solutions

• Ask an Alisco Specialist

• Visit the DuPont Stand Hall 5 A40

• Questions?elaina.harvey@dupont.com+44 7881 836588

This information corresponds to our current knowledge on the subject and may be subject to revision as new knowledge becomes available. It is your responsibility to investigate other sources of information on this issue that more appropriately addresses your product and its intended use. DuPont makes no warranties and accepts no liability whatsoever. This information is not intended for use by you or others in advertising, promotion, publication or any other commercial use.

Disclaimer Notice

8