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LIGHTNING & LIGHTNING PROTECTION ITS HEARTLAND CONFERENCE MARCH 27, 2013 BUD VANSICKLE LIGHTNING PROTECTION INSTITUTE

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LIGHTNING & LIGHTNING PROTECTION

I T S H E A R T L A N D C O N F E R E N C EM A R C H 2 7 , 2 0 1 3

B U D VA N S I C K L EL I G H T N I N G P R O T E C T I O N I N S T I T U T E

Lightning strikes the United States 20 million times each year.

A bolt of lightning can generate heat in excess of 50,0000 F.

Lightning travels 90,000 miles per SECOND.

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& F

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Dev

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Dev

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Empi

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Wha

t is

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Ana

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Neg

ativ

e Li

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Pos

itive

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Clo

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und

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NASA Global Lightning 1995 -2002

Flas

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ensi

ty M

aps

1996 -2004

Flas

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aps

2009

lightning related – Insurance Information Institute

(I.I.I.)

Annual property losses due to lightning in the

United States exceeded $1.03 billion in 2010 (2011

$.952 billion) – I.I.I.

213,000 insurance claims for lightning damage were

paid in 2010, (186,000 in 2011) avg. claim up 5% -

I.I.I.

The FAA estimates that lightning costs the airlines

$2 billion annually in operating costs and passenger

delays.

Lightning is the leading cause of all church fires.

Lightning is one of the leading causes of weather

Saf

ety

& E

cono

mic

C

onse

quen

ces

Ligh

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otec

tion

NFPA 780: Standard for the Installation of Lightning Protection Systems

UL96A: Installation Requirements for Lightning Protection Systems

LPI 175: Lightning Protection Institute –Standard of Practice

Inst

alla

tion

Stan

dard

s

Strike Termination Devices

Conductors

Ground Terminations

Bonding Connections

Surge Protection Devices (SPD)

Five

Ele

men

ts

NFPA ROLLING SPHERESt

rikin

g D

ista

nce

Stepped Leader

Corners, edges, ridges of structures naturally accumulate ions in the electrical field, so they are likely candidates for lightning attachments. Tall slender items disrupt the field in the same manner, releasing ions easily or providing leaders for the lightning stroke

National Geographic Photo

NFPA ROLLING SPHERESt

rikin

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ista

nce

EFFECTS OF CURRENT FLOW THROUGH A CONDUCTOR

Current flow through an impedance leads to a voltage.An electric field (E) will develop.A magnetic field (B) will develop.Coupling (capacitive & inductive) can occur through these fields.

Vo

V

I B

SIDEFLASH

An electric field can develop between the conductor and nearby objects, at different electrical potential.Once the field value exceeds a breakdown value, Ebr, sideflash, or arcing, can occur.Air breakdown:Ebr ~ 1 MV/m

Vo

V

I VoE

r

BONDING

Ideal electrical connection results in equipotential. Since no electrical potential (voltage) difference exists, no field is developed, preventing flashover.In reality, connection is imperfect (since bonding conductor has impedance) so field will be minimized.

Vo

V

I V

HOW SURGE OCCURS – MAGNETIC FIELD COUPLING

Service conductors in a magnetic field can have a current (and consequently a voltage) induced upon it, particularly if it’s parallel to the current path.

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V

I

B

Ii

OPERATION OF THE GROUNDING SYSTEM

GROUNDING ELECTRODE (GROUND ROD)

CONDUCTOR

GRADE

Consider current injection into the grounding electrode.

I

OPERATION OF THE GROUNDING SYSTEM

GRADE

I

CURRENT FLOWS THROUGH ‘SHELLS’ OF EARTH, EACH WITH A RESISTANCE.I I

RR R R R R R R

v v v vvv v v

A VOLTAGE DEVELOPS ACROSS EACH SHELL

OPERATION OF THE GROUNDING SYSTEM

GRADE

I

I I

RR R R R R R R

v v v vvv v v

STEP POTENTIAL V1 – V2

GRADE

V

HOW SURGE OCCURS – GPR EFFECTS

V1 V2

Unbonded grounding systems can develop severe voltage differences. If connected within a structure, very high currents can develop leading to magnetic coupling or arcing within equipment.

Pers

onal

Saf

ety

Step Voltage

AVERAGE NUMBER OF U.S. LIGHTNING DEATHS*SINCE THE CAMPAIGN BEGAN (2000)

50

55

60

65

70

75

00 01 02 03 04 05 06 07 08 09 10 11 12

Deaths

Year

*30-year average

2012 Lightning Deaths: A Closer Look

• 89% were male• 6 were children• 7 were on fishing trips• 7 left safe shelter or were steps

away• 6 were in or near water• 12 were under or near trees• Many were resuscitated but died

later

Lightning Deaths in 17 States

Leon

the

Lig

htni

ng L

ion

The

End

Phone: 800-488-6864 E-mail: [email protected] Website: www.lightning.org

Bud VanSickle                   Lightning Protection Institute

Quality Program   General• Exam program for certification• LPI‐IP field inspection program• 4 National tradeshows• A&E information CD• NFPA, UL STP, IEC Committees• Annual Conference• Research funding• LPI 175 Installation & 177 

Inspection Standards

Communication• Newsletters & E‐blasts• Brochures & materials• Feature articles• DVDs “infomercials”• Releases on national wire services• Lightning Safety Awareness Week• “Leon” the lightning lion• I.I.I., IBHS, & FLASH – insurance 

industry

Website• Find an Installer• FAQ• Links• Specifications

• Research papers• Non‐compliant systems• Educational tools – Children’s section• Store• Blog