AS/NZS 1768:2007 vs AS 1768:2021
AS/NZS 1768:2007 is superseded in Australia by AS 1768:2021 and still current in New Zealand. Which edition governs your project depends on the site's country and on how your contract cites the standard.
AS/NZS 1768:2007 is the joint Australian and New Zealand lightning protection standard. Standards Australia replaced it on 3 December 2021 with AS 1768:2021, which is an Australian Standard only.
A 2007 citation is correct for a New Zealand site and out of date for an Australian one. The AS 1768:2021 Preface records that it was prepared to supersede the joint standard, often written simply as AS NZS 1768. Standards New Zealand kept the 2007 edition current, so the same number now names two lightning protection standards, 14 years apart.
AS 1768:2021 publishes no clause-by-clause change list. The differences on this page are the ones its Preface, Clause 2.5.3 and Clause 4.5 state, and we describe no 2007 content beyond them.
Is AS/NZS 1768:2007 still current?
No in Australia, yes in New Zealand. Both answers come from the standards bodies themselves.
Superseded by AS 1768:2021
The Preface of AS 1768:2021 says the Australian members of the joint committee EL-024, Protection Against Lightning, prepared it to supersede AS/NZS 1768:2007. It was approved on 23 November 2021 and published on 3 December 2021. For new work in Australia, the 2021 edition is the current standard.
Still current
Standards New Zealand's listing for AS/NZS 1768:2007 says the Australian review produced an Australia-only standard and that the 2007 edition remains current in New Zealand. A New Zealand site is not out of date for citing it.
The title page of AS 1768:2021 traces the whole line: first issued in Australia as AS MC1 in 1969, redesignated AS 1768 in 1975, a third edition in 1991, joint interim AS/NZS 1768(Int):2003, joint AS/NZS 1768:2007, and finally AS 1768:2021. Only the last step dropped the NZS from the name.
Which edition applies to your project
The edition that governs is the one the controlling document names, read against the site's country. With no edition named, Australia means AS 1768:2021 and New Zealand means AS/NZS 1768:2007.
| Situation | Edition that applies | Basis |
|---|---|---|
| New work in Australia, no edition named | AS 1768:2021 | AS 1768:2021 Preface: prepared to supersede AS/NZS 1768:2007 |
| Work in New Zealand, no edition named | AS/NZS 1768:2007 | Standards New Zealand lists the 2007 edition as current in New Zealand |
| A contract or specification that cites AS/NZS 1768:2007 by date | The 2007 edition, as written, until the parties agree a change | The document's own wording. General contract practice, not a rule of either standard |
| A contract that cites AS 1768 or AS/NZS 1768 with no date | Not settled by either standard. Confirm which edition the specifier intends | Ask the specifier in writing. An undated reference in Australia points to a different text than in New Zealand |
| A New Zealand project whose specification names AS 1768:2021 | AS 1768:2021, by contract | The project specification. The 2021 edition is not a New Zealand standard, so the contract is what brings it in |
| A regulation, licence condition or regulator guideline that cites AS/NZS 1768:2007 | Whatever that instrument names, until it is amended | The instrument's own text. Read it on the official legislation site and ask the regulator before relying on a newer edition |
| A New Zealand project that specifies IEC 62305 | IEC 62305, not either AS 1768 edition | The project specification. The risk assessment is IEC 62305-2 |
We have deliberately not named any Australian regulation here. Before you treat any regulation as requiring one edition or the other, read the current consolidated text on the state or federal legislation site, and check whether it refers to the standard by date.
What to do when a specification cites AS/NZS 1768:2007
Do not quietly swap editions. The document you were given is the contract, and changing its standard on your own moves risk onto you. Work through it in this order.
1. Check where the site is. In New Zealand the 2007 edition is current, so the reference is not stale and you design to it. In Australia it is superseded, so the question is whether the specifier meant that edition or simply copied an old clause.
2. Read how the reference is written. A dated reference names one text. An undated reference names no edition, and neither standard says which one it means, so treat it as an open question. A dated 2007 reference in a master specification last revised before December 2021 may simply predate the 2021 edition, so ask.
3. Ask in writing. Send a request for information that names both editions and asks which governs. Record the answer. If a regulator's document is involved, ask the regulator, not the client.
4. Treat an imported specification as a contract choice. A New Zealand client who hands you an Australian specification naming AS 1768:2021 has chosen that edition by contract. Confirm the choice was deliberate, then design to it and say so on the report.
5. Keep the work consistent. Run the risk assessment, air terminal placement and surge protection all under one edition. A report that mixes location categories from an earlier edition with a 2021 risk result is defensible under neither.
6. Write the edition on the report. State it in one line a reviewer can check, for example: assessed to AS 1768:2021, risk method of Appendix B using the spreadsheet supplied with the standard, with the clauses relied on listed. Add the spreadsheet version you ran, so a reviewer years later knows exactly what the figures mean.
Why AS 1768 became an Australia-only standard
The 2021 edition was prepared within the joint committee EL-024, Protection Against Lightning, but only by its Australian members. The AS 1768:2021 Preface records that both standards bodies consulted stakeholders in Australia and in New Zealand, and then chose to issue the revision under the Australian label alone instead of as another joint AS/NZS document.
The Preface gives no reasons for that decision. Its practical effect is plain: there is no New Zealand adoption of the 2021 text, so New Zealand kept the edition it already had.
For New Zealand's own position, including where IEC 62305 comes in, see lightning protection in New Zealand. For the Australian standards that sit around AS 1768:2021, see lightning protection standards in Australia.
The differences AS 1768:2021 records
Each row is a change the 2021 text states about itself, with the clause that says so.
| Change | What the 2021 edition records, in our words | Where it says so |
|---|---|---|
| Surge protection locations | The lightning location categories of earlier editions give way to lightning protection zones, LPZ0A to LPZ 2...n, with SPDs at each zone boundary | Clause 4.5, Table 4.1 note a |
| The risk spreadsheet | First issued with AS/NZS 1768:2007, now enhanced for clarity and function, and supplied with the purchased standard | Preface, Clause 2.5.3 |
| The main change | Recognises how buildings are built today, and accepts that many modern buildings already protect themselves against lightning | Preface |
| Size of the revision | Described as a major revision of the earlier versions, aiming to bring the document in line with IEC standards | Preface |
| Scope of the standard | An Australian Standard only, prepared to supersede the joint AS/NZS 1768:2007 after consultation in both countries | Preface |
Table 4.1 in AS 1768:2021 keeps the old location category letters (A, B, C1 to C3) beside the zone boundaries, so a reader of an older schedule can map one to the other. Its note a refers to previous editions of AS/NZS 1768 without saying which one introduced the categories.
What a self-protecting building means under AS 1768:2021
The headline change in the Preface is easy to misread as permission to skip lightning protection on steel or concrete buildings. AS 1768:2021 does not say that. The risk calculation in Clause 2.5.3 takes a structure built wholly of metal or of reinforced concrete to be electrically continuous, properly earthed and already fitted with enough air terminations. When the spreadsheet then reports that no direct strike protection is needed, that result rests on those assumptions being true.
So Clause 2.5.3 sends you back to the building. Continuity and earthing must still meet Sections 3 and 5, and someone has to confirm the air terminations are actually there. Clause 3.2.2.3 sets out which parts of a structure may serve as natural air terminals, such as sheet metal cladding, metal handrails, tanks and parapets, provided they meet Clause 3.1 and the sizes in Table 3.3. Its note is blunt: a reinforced concrete roof on its own cannot do the job without metal items or dedicated air terminals.
The same idea appears for large sites. Clause 2.5.4 says standalone metal structures in an open facility, such as tanks and pipework, are normally self-protecting, and recommends protecting the equipment and cables linking them under Section 4. For how the 2021 edition places air terminals, see AS 1768 air terminal placement.
What a reader of the 2007 edition should check in AS 1768:2021
These are the parts of the 2021 edition that decide a design or a report today. Read them in the 2021 text before you reuse anything from a 2007-era design.
The risk method
Four types of loss, each judged against its own tolerable value in Table 2.1, which credits IEC 62305-2:2010 Table 4. Appendix B gives a simplified form of the IEC method for Australian conditions, and Appendix C works the examples.
Air terminal placement
The rolling sphere method is the placement method, set out in Appendix D, which is normative. Clause 3.2.2.2 has vertical rods at least 500 mm long, and requires the rolling sphere check under Appendix D.
Conventional systems only
The 2021 edition covers conventional systems and does not endorse air terminals sold on claims of enhanced performance. Whatever a product claims, air terminals must still be placed by Section 3 to conform.
Surge protection by zone
SPDs are rated by the zone boundary they sit on (Table 4.1 for a.c. power, Table 4.2 for signal and data lines) and installed to Appendix F, which is normative. See AS 1768 surge protection.
Testing and maintenance
Clause 5.4.4 recommends an inspection at least every two years, more often in corrosive places such as marine sites, and after any change to the structure or the system, or after a strike.
Specific structures
Clause 1.1.2 points to appendices for specific structures (I), explosive or flammable contents (J, normative), wind turbines (K), high voltage power systems (L), mines (M) and solar PV (N).
Of the fourteen appendices in AS 1768:2021, three are normative and so form part of the requirements: Appendix D (air terminal placement), Appendix F (SPD installation) and Appendix J (explosives, flammable gases, vapours and combustible dusts). The rest are informative. Earthing sits in informative Appendix E; see AS 1768 earthing. For the whole 2021 standard section by section, read AS 1768 explained.
Is the 2021 risk assessment different from the 2007 one?
Treat a 2007 risk result as historical: AS 1768:2021 publishes no comparison of its figures with 2007 figures, so no source can tell you a 2007 result would come out the same. Clause 2.5.3 records that the spreadsheet carrying out the assessment was first issued with AS/NZS 1768:2007 and has been enhanced for clarity and function since. Clause 2.2 says its calculations come from IEC 62305-2, adjusted for Australian conditions, and Clause 2.5.3 describes the Appendix B approach as a simplification of the IEC method with fewer variables and options.
The IEC lineage matters. The Preface's aim of alignment with IEC standards does not point to the current IEC 62305-2:2024. Where AS 1768:2021 names an IEC source for its risk values, it names the 2010 edition: Table 2.1 credits IEC 62305-2:2010 Table 4 for its tolerable risks, one for each of four types of loss. Table 2.2 lists the risk components RA, RB, RC, RM, RU, RV, RW and RZ, while Appendix B works with its own set of letters (Rh, Rs, Rw and others).
If an existing report was prepared under AS/NZS 1768:2007 and the site is in Australia, run the assessment again under AS 1768:2021 with its own spreadsheet. The decision, as Clause 2.2 reminds you, still calls for judgement from the user.
Common mistakes with the two editions
Most problems with AS/NZS 1768:2007 and AS 1768:2021 come from assuming the name tells you the country, the date or the method.
Applying the 2021 edition in New Zealand by default
AS 1768:2021 is not a New Zealand standard. Unless the project adopts it by contract, a New Zealand site sits under the current joint edition, AS/NZS 1768:2007, or under IEC 62305 where specified.
Trusting a 2007-era PDF that says it is current
Guides written before December 2021 still rank and still call the joint edition current. For an Australian site that stopped being true when AS 1768:2021 was published.
Taking IEC alignment to mean the 2024 IEC edition
The risk values AS 1768:2021 credits to IEC come from IEC 62305-2:2010. An IEC 62305-2:2024 result is a different assessment, not a check on an AS 1768 one.
Treating a self-protecting building as needing no checks
Clause 2.5.3 still requires continuity and earthing to Sections 3 and 5 and the air terminations confirmed on site. The spreadsheet's answer assumes them; it does not prove them.
Old location categories in a new SPD schedule
A 2021 design specifies SPDs by zone boundary (Clause 4.5 and Table 4.1). Category letters alone, with no zone named, suggest a schedule carried over from an earlier edition.
Carrying an old risk result forward
A risk figure computed under the 2007 edition says nothing reliable about the 2021 method. In Australia, rerun it on the 2021 spreadsheet and record the edition used.
Lumex runs AS 1768:2021, not the 2007 method
Lumex runs the AS 1768:2021 risk assessment only. Lumex's engine, Voltrace, computes each of R1 to R4 against its own tolerable value, then searches for the least protection that brings all four within their limits, as Clause C.3.4.2 lays out, and shows the working behind every figure in a report the signing engineer approves. It does not run the AS/NZS 1768:2007 method, and it does not design the air terminals, conductors or earthing, or certify a structure.
To bring an Australian site forward, enter the building once, get a 2021 result with its clause references, and set a review date (24 months for AS 1768 in Lumex) so the assessment does not go stale again. For a New Zealand project that specifies IEC 62305, Lumex runs the assessment as IEC 62305-2:2024. A New Zealand project on AS/NZS 1768:2007 is outside what Lumex runs today.
Both standards are copyrighted. Buy AS 1768:2021 from Standards Australia, and AS/NZS 1768:2007 from Standards New Zealand, for any design or certification work. Lumex is independent of both bodies. Not sure which standard your project falls under? Start with which lightning protection standard applies. Then run your Australian site through the AS 1768:2021 risk assessment in Lumex.
Questions answered
Is AS/NZS 1768:2007 still current?
What replaced AS/NZS 1768:2007?
What changed in AS 1768:2021?
Does AS 1768:2021 apply in New Zealand?
My specification cites AS/NZS 1768:2007. What should I do?
Is the 2021 risk assessment different from 2007?
Does AS 1768:2021 follow IEC 62305-2:2024?
What came before AS/NZS 1768:2007?
Lumex computes the method of the standard you choose, IEC 62305-2:2024, AS 1768:2021 or NFPA 780-2026, and shows the working. It does not certify a structure. You may not issue or submit a Lumex output until a competent person, qualified where the structure is located, has reviewed the inputs and the result and signed it.
AS 1768:2021 Table 2.1 sets a tolerable value for each type of loss, and the owner chooses the one for economic loss. Every AS 1768 assessment in Lumex states the values that applied.
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