Lightning Protection System Building Codes & Rules

- Lightning Protection System Tools™ simplifies the National Construction Code (NCC) with interactive graphics, including deemed to comply & best practices.

FFL

AS 1768:2021, 3.1

AS 1768:2021, A.6

Lightning Protection System (LPS)^{AS 1768:2021, 3.1AS 1768:2021, A.6}

May be composed of
Components of the structure, or
A dedicated system, or
A combination of both
Components
Continuous electrical connection
Follows correct spacing, material & sizing

AS 1768:2021, 3.2

Air Termination^{AS 1768:2021, 3.2}

AS 1768:2021, A.6 (c)

Test Link^{AS 1768:2021, A.6 (c)}

Locate between Downconductors & Earth Electrodes

Equipotential Bonding

Bond metal installations with LPS at each end^[1]
At ≤ 10m vertical intervals, if^[2]
> 10m vertical metal installations through a structure, &
< 1m from Downconductor

Lightning Protection Bonding RULES

NCC 2022 V2

All Building Classes

NCC 2022 S1, S13, C3D14, C4D15, J2D2, 13.4

[2019 Sch 5, Spec C3.15, C2.3, C3.15, J0.1, 3.12]

May 2023

AS 1768:2021, E.3.9.1

AS 1768:2021, 3.7.4

AS 1768:2021, 3.3.3 (c)

AS 1768:2021, 3.6.2

AS 1768:2021, E.3.9

Building elements requiring energy use to be protected, secure, & energy efficient to the NCC
Links conductive parts to avoid unregulated discharge
≤ 1.5m^{AS 1768:2021, E.3.9.1} Conductor length to Main Earth Bar
≤ 10m^{AS 1768:2021, E.3.9.1} Bonding conductor length
Bonding Conductor Size (section dimension)^{AS 1768:2021, 3.7.4}
≥ 16mm² Major Bonding Conductor
≥ 6mm² Minor Bonding Conductor
Bonding for Curtain Wall^{AS 1768:2021, 3.3.3 (c)}
Must be electrically isolated
20m intervals on the perimeter
10m intervals at the top & bottom of each Curtain Wall
Metal parts of the structure that need to be bonded^{AS 1768:2021, 3.6.2}
Outstanding Roof elements
Hazardous metal components of the structure
Balcony Rail
Ladder
Walkway Gantry
Screens
Conductive Service Pipes
Gas
Water
Bonding Methods^{AS 1768:2021, E.3.9}
Bonding Bar
Natural Components as Common Bonding Network
Ring Earth

AS 1768:2021, 3.6.2

Bond metal installations with LPS at each end^{AS 1768:2021, 3.6.2}
At ≤ 10m vertical intervals, if^{AS 1768:2021, 3.6.2}
> 10m vertical metal installations through a structure, &
< 1m from Downconductor

AS 1768:2021, 3.3

Down Conductor^{AS 1768:2021, 3.3}

AS 1768:2021, 3.5

Earth Termination^{AS 1768:2021, 3.5}

AS 1768:2021, 3.1

Ligntning Protection System^{AS 1768:2021, 3.1}

Side Strike Protection

For Tall Structures ≥ 60m height^[1]
Position on vertical sides of building
For ≤ 70m building height, at ≥ 60m^[2]
For ≥ 75m building height, at top 20% of structure^[3]

Side Strike PROTECTION

NCC 2022 V2

All Building Classes

NCC 2022 S1, S13, C3D14, C4D15, J2D2, 13.4

[2019 Sch 5, Spec C3.15, C2.3, C3.15, J0.1, 3.12]

May 2023

AS 1768:2021, 3.2.4

Building elements requiring energy use to be protected, secure, & energy efficient to the NCC
Protect projecting elements such as^{AS 1768:2021, 3.2.4}
Corners & facade edges
Balconies
Viewing Deck
May be the structure's natural elements, like Metal Cladding^{AS 1768:2021, 3.2.4}
Bond to LPS regardless of the building height

Air Terminal RULES

NCC 2022 V2

All Building Classes

NCC 2022 S1, S13, C3D14, C4D15, J2D2, 13.4

[2019 Sch 5, Spec C3.15, C2.3, C3.15, J0.1, 3.12]

May 2023

AS 1768:2021, 3.2.3

Building elements requiring energy use to be protected, secure, & energy efficient to the NCC
Air Terminal to be placed on vulnerable parts of the structure^{AS 1768:2021, 3.2.3}
Pointed Apex Roof
Spires
Protrusions
Gable Roof Ridge Ends
Other vulnerable parts
Horizontal Roof exposed edges
Gable Roof edges
Points & corners flat surfaces
Intruding surfaces

Air Terminal Network / System

Seizes lightning stricke to a favoured spot
Allows discharge current to be directed from the Downconductor to the Earthing System
May comprise of Conductive components of the structure, if requirements are met
Parapet
Ornaments
Handrails
Part of Roof

AS 1768:2021, 3.2.4

AS 1768:2021, 3.2.4 (a)

AS 1768:2021, 3.2.4 (b)

For Tall Structures ≥ 60m height^{AS 1768:2021, 3.2.4}
Position on vertical sides of building
For ≤ 70m building height, at ≥ 60m^{AS 1768:2021, 3.2.4 (a)}
For ≥ 75m building height, at top 20% of structure^{AS 1768:2021, 3.2.4 (b)}

Air Terminal / Lightning Rod

≥ 500mm^[1] length of vertical Rod
≥ 35mm²^[2] section dimension
Position, number, & height to be determined through the Rolling Sphere Method (RSM)^[3]
Verify system design with your Electrical Consultant

Air Terminal RULES

NCC 2022 V2

All Building Classes

NCC 2022 S1, S13, C3D14, C4D15, J2D2, 13.4

[2019 Sch 5, Spec C3.15, C2.3, C3.15, J0.1, 3.12]

May 2023

AS 1768:2021, 3.2.3

Building elements requiring energy use to be protected, secure, & energy efficient to the NCC
Air Terminal to be placed on vulnerable parts of the structure^{AS 1768:2021, 3.2.3}
Pointed Apex Roof
Spires
Protrusions
Gable Roof Ridge Ends
Other vulnerable parts
Horizontal Roof exposed edges
Gable Roof edges
Points & corners flat surfaces
Intruding surfaces

Air Terminal Network / System

Seizes lightning stricke to a favoured spot
Allows discharge current to be directed from the Downconductor to the Earthing System
May comprise of Conductive components of the structure, if requirements are met
Parapet
Ornaments
Handrails
Part of Roof

AS 1768:2021, 3.2.2.2 (a) (ii)

AS 1768:2021, 3.7.4

AS 1768:2021, 3.2.2.2 (b)

≥ 500mm^{AS 1768:2021, 3.2.2.2 (a) (ii)} length of vertical Rod
≥ 35mm²^{AS 1768:2021, 3.7.4} section dimension
Position, number, & height to be determined through the Rolling Sphere Method (RSM)^{AS 1768:2021, 3.2.2.2 (b)}
Verify system design with your Electrical Consultant

Downconductors

≥ 2 Downconductors every LPS^[1]
≤ 20m Intervals^[2]
≥ 35mm² section dimension^[3]

Downconductor RULES

NCC 2022 V2

All Building Classes

NCC 2022 S1, S13, C3D14, C4D15, J2D2, 13.4

[2019 Sch 5, Spec C3.15, C2.3, C3.15, J0.1, 3.12]

May 2023

AS 1768:2021, 3.3.2

AS 1768:2021, 3.3.3

AS 1768:2021, A.6 (b)

Building elements requiring energy use to be protected, secure, & energy efficient to the NCC
Requirements or Downconductors^{AS 1768:2021, 3.3.2}
Follow direct path to Earth Termination
Space equally
Do not locate in Lift Shafts & Service Ducts
Restrict from Public access

Structure's Natural Components^{AS 1768:2021, 3.3.3}

May be used as downconductors
As long as they are electrically connected
Material & sizing requirements shall be met
Structural Steel Frame
Metal Cladding except if core is combustible
Curtain Wall System
Steel Reinforcement in Concrete
Lighting & Communication Towers
Roadway Gantries

Downconductor System^{AS 1768:2021, A.6 (b)}

A path of low impedance from Air Termination to the Earth Termination System
Prevents excessively large volategs from developing
As direct as possible without sharp bends & stress points

AS 1768:2021, 3.3.2 (b)

AS 1768:2021, 3.3.2 (a)

AS 1768:2021, 3.7.4

≥ 2 Downconductors every LPS^{AS 1768:2021, 3.3.2 (b)}
≤ 20m Intervals^{AS 1768:2021, 3.3.2 (a)}
≥ 35mm² section dimension^{AS 1768:2021, 3.7.4}

Lightning Earth Electrodes

≥ 3m^[1] Separation Distance from other Earthed Services
≥ 500mm depth from FFL^[2]
≥ 35mm² Section Dimension^[3]
Corrosion-resistant^[4]
With durable tag stating^[5]
LIGHTNING EARTH - DO NOT DISCONNECT

LPS Earth Electrode RULES

NCC 2022 V2

All Building Classes

NCC 2022 S1, S13, C3D14, C4D15, J2D2, 13.4

[2019 Sch 5, Spec C3.15, C2.3, C3.15, J0.1, 3.12]

May 2023

AS 1768:2021, 3.5.2 (a)

AS 1768:2021, 3.5.2 (d)

AS 1768:2021, 3.5

AS 1768:2021, 3.5.2

Building elements requiring energy use, to be protected, secure, & energy efficient to the NCC
Entire Earthing System to be bonded to Earth Termination Network^{AS 1768:2021, 3.5.2 (a)AS 1768:2021, 3.5.2 (d)}

Earth Termination Network / System^{AS 1768:2021, 3.5}

Must have low impendance to disperse energy
Systems vary depending on site geographical condidtions
Should minimise the risk of injury & damage to equipment
May be comprise of the structure's natural components
Unobstructed by continuous isolating barriers such as^{AS 1768:2021, 3.5.2}
Screw Anchors
Steel Piles
Reinforced Concrete Footings
Other conductive structural supports

AS 1768:2021, E.3.8

AS 1768:2021, 3.7.4

AS 1768:2021, 3.5.2

AS 1768:2021, 3.5.2 (c)

AS 1768:2021, 3.7.1

≥ 3m^{AS 1768:2021, E.3.8} Separation Distance from other Earthed Services
≥ 500mm depth from FFL^{AS 1768:2021, 3.7.4}
≥ 35mm² Section Dimension^{AS 1768:2021, 3.5.2}
Corrosion-resistant^{AS 1768:2021, 3.5.2 (c)}
With durable tag stating^{AS 1768:2021, 3.7.1}
LIGHTNING EARTH - DO NOT DISCONNECT