Metric Conversion Act 1972

Definitions: The Act contains two defined terms (s 3). "Metric system of measurement" is a substantive definition. It comprises three categories: (a) units of the International System of Units as approved by the General Conference on Weights and Measures; (b) units decimally related to those units and for the time being so approved; and (c) any other units declared from time to time under the Commonwealth Metric Conversion Act 1970 or any Commonwealth Act in substitution (s 3). The other defined term is "statutory instrument", which is defined broadly to include proclamations, Orders in Council, regulations, rules, local laws, by‑laws, notices, orders or other instruments promulgated under or for the purposes of any Act (s 3). The statutory definition therefore authorises amendments to a wide variety of subordinate instruments.

Governor’s power to amend Acts: Section 5 authorises the Governor, when of the opinion it is necessary or expedient to give proper effect to an Act’s purposes, to amend any reference in an Act to a physical quantity that is not in metric units by substituting a reference expressed in metric units (s 5(1)). The power operates notwithstanding other Acts or laws (s 5(1)), subject to procedural constraints. Proclamations may take effect on specified dates not earlier than publication in the Government Gazette (s 5(2)(a)). Substitution may alter the physical quantity, but only within a margin of plus or minus 10 per cent of the original quantity (s 5(2)(b)(i)-(ii)). The Governor’s proclamation must be tabled in each House within six sitting days after Gazette publication (s 5(3)), and each House may disallow the proclamation within a further short window (s 5(4)). Disallowance operates prospectively from that point but does not invalidate actions taken in good faith before disallowance (s 5(4)).

Ministerial/Governor approval for statutory instruments: Section 6 permits the Minister who administers the Act under which a statutory instrument was made to amend references in that instrument by Gazette notice with the Governor’s approval (s 6(1)). The procedural rules in s 5(2)-(4) apply to notices under s 6 as though they were proclamations (s 6(2)). That applies the same effect‑dating, numeric tolerance and parliamentary laying and disallowance procedure to statutory instrument amendments.

Regulation power for subsidiary legislation: Section 7 (inserted in 2009) permits the Governor, on the Minister’s recommendation, to make regulations amending any subsidiary legislation made under any Act (s 7(1)). The Minister may recommend only if each proposed amendment is solely for substituting metric references (s 7(2)). Section 7(3) repeats the ±10% tolerance for the substituted quantity. The Act therefore creates three executive pathways with similar substantive limits and parliamentary oversight: proclamations for Acts, notices for statutory instruments, and regulations for subsidiary legislation.

Notwithstanding clause and good‑faith preservation: Both s 5(1) and s 6(1) begin by stating the power operates notwithstanding other Acts or laws, thereby prioritising the conversion power when used for its stated purpose. Section 5(4) preserves actions taken in good faith before disallowance, insulating prior executive action from retrospective invalidation.

Omissions and spent provisions: Section 4 is omitted under the Reprints Act 1984 (noted in the statute text). The compilation notes state that the First to Fourth Schedules set out amendments effected by s 4 and are now spent and omitted. Practitioners relying on historical detail should consult the compilation table and notes (Compilation table; Notes).

Interplay with Commonwealth law: The definition of metric units explicitly invokes Commonwealth declarations (s 3(c)), and the Act’s notes record that the Commonwealth Metric Conversion Act 1970 was repealed and replaced by national weights and measures amendments (Notes, note 3). The Act thus contemplates that Commonwealth legislative or administrative declarations about metric units will feed into the definition used in this State Act.

Core constraints: The central operational constraints in the Act are the subjective threshold for executive action ("opinion that it is necessary or expedient" in s 5(1)), the numeric tolerance of ±10% for substituted quantities (s 5(2)(b); s 7(3)), the requirement that changes cannot take effect earlier than Gazette publication (s 5(2)(a)), and the parliamentary laying and disallowance windows (s 5(3)-(4); s 6(2)). These are the statutory levers that define both the reach and limits of the metric conversion powers.

Primary decision‑makers: The Act vests primary decision authority in the Governor, acting by proclamation (s 5), and in Ministers, acting with the Governor’s approval via Gazette notice (s 6) or by making a Ministerial recommendation that results in regulations made by the Governor (s 7). The Minister administering the Act that an amended statutory instrument concerns is the responsible official for issuing a notice under s 6(1). The Governor’s regulatory power under s 7 requires a Ministerial recommendation, and the Minister is constrained to recommend only if the proposed changes are "solely" for metric substitution (s 7(2)). Thus the executive branch bears decision responsibility and the administrative burden of initiating, publishing and tabling amendments.

Parliament: Both Houses receive copies of proclamations and Gazette notices under s 5(3) and s 6(2) (application of s 5(3)). Each House has an express disallowance power: if within the prescribed sitting‑day window a House passes a resolution disallowing the proclamation or notice, the instrument ceases to have effect (s 5(4); s 6(2) applying s 5(4)). Parliament therefore exercises retrospective oversight rather than prior authorisation, with a narrowly defined timeframe for action (see procedural timings below). Practitioners should note Parliament’s role is limited to disallowance after laying, rather than providing pre‑approval.

Public and private parties regulated by statutory thresholds: Entities subject to Acts, statutory instruments or subsidiary legislation that contain references to physical quantities will be affected when those references are amended. The Act authorises substitution of metric quantities for previously non‑metric quantities in primary and subordinate law (s 5(1); s 6(1); s 7(1)-(3)). This includes regulatory thresholds, measurement requirements, licensing quantities, fees expressed by measure, exemptions keyed to quantities and other statutory references to physical quantities. The Act does not itself create offences or new private rights; its amendments alter the underlying instruments that do.

Administrations and regulators: Government agencies, local governments, boards and tribunals that administer Acts and statutory instruments are affected because they will need to implement, interpret and enforce the substituted metric quantities. Section 3’s definition of "statutory instrument" includes local laws and by‑laws (s 3), which places local government instruments squarely within the scope of the power created by s 6 and s 7. Where subsidiary legislation under local or state laws contains non‑metric measures, the regulation and notice powers permit updating those references.

Legal practitioners and contract parties: Because the Act permits statutory conversions that may alter prescribed quantities within ±10%, lawyers and commercial parties whose obligations, licences or entitlements are defined by statute may be affected. The Act’s text does not expressly address the legal effect on pre‑existing contracts or rights that refer to statutory quantities, but practitioners will need to consider whether an amended statutory threshold alters obligations or entitlements that are tied to the statutory definition.

Standards authorities and weights and measures bodies: The Act’s definition of metric system expressly links to units approved by the General Conference on Weights and Measures and to Commonwealth declarations (s 3(a)-(c)). National standards or Commonwealth determinations consequently influence which units are available to be substituted under this Act. Where a Commonwealth Act substitutes or declares units, those declarations feed into the State definition (s 3(c); Notes).

Who bears compliance costs: The immediate administrative cost of making amendments , preparing proclamations, notices and regulations and publishing them in the Government Gazette , falls on the relevant government departments and Ministers. The downstream compliance costs of changed thresholds, signage, forms, licences and enforcement fall on regulated parties, including businesses and local governments, to the extent that those matters refer to the substituted measurements. The Act does not itself appropriate funds or specify compensation mechanisms for affected private parties.

Duties of the executive to follow procedural steps: When exercising the s 5 proclamation power the Governor must ensure any proclamation takes effect on a date not earlier than the day of Government Gazette publication (s 5(2)(a)). The Minister administering the affected Act must cause a copy of the proclamation to be laid on the Table of each House of Parliament within the first six sitting days of that House after Gazette publication (s 5(3)). Section 6 applies the same procedural obligations and timelines to notices amending statutory instruments (s 6(2) applying s 5(2), (3) and (4)). For subsidiary legislation changes via s 7 regulations, the Governor makes the regulation on the Minister’s recommendation, and the Minister may recommend only if the amendment is solely for metric substitution (s 7(1)-(2)). The Governor and Minister therefore have statutory duties to adhere to the effect‑dating, publication and tabling requirements and to limit changes to metric conversion purposes where required (s 6(1); s 7(2)).

Numeric constraint duty: A statutory duty exists as a limit rather than an obligation. Any substituted physical quantity must not be more than 10% greater than or less than the quantity replaced (s 5(2)(b)(i)-(ii); s 7(3)). That numeric tolerance constrains executive discretion to avoid large deviations from existing statutory measures.

Parliamentary right to disallow: Each House of Parliament has the right to pass a resolution disallowing a proclamation or notice within the specified times (s 5(4); s 6(2) applying s 5(4)). If a House disallows, the proclamation or notice ceases to have effect from that point. The Act also preserves actions taken in good faith before disallowance, so Parliament’s right is a prospective check (s 5(4)). The statutory timeline limits Parliament to retrospective oversight within a short window after the proclamation or notice is tabled (s 5(3)-(4)).

Ministerial recommendation constraint: For regulation amendments to subsidiary legislation, the Minister has the constraint that a recommendation under s 7(1) may be made only if the Minister considers each proposed amendment is solely for the purpose of metric substitution (s 7(2)). This places a legal boundary on the scope of changes that may be combined with metric conversion under the regulations pathway.

Expression of opinion as statutory threshold: The Governor’s power under s 5(1) is framed by the Governor being of the opinion that the amendment is "necessary or expedient so to do for giving proper effect to the purposes for which an Act was enacted". That subjective standard is the statutory threshold for the exercise of power. The Act does not prescribe criteria for that opinion or require the publication of reasons, but the procedure requires tabling and leaves room for parliamentary review by disallowance.

Notwithstanding other laws: Sections 5(1) and 6(1) begin "Notwithstanding the provisions of any other Act or law", which creates a statutory right to override conflicting provisions for the limited purpose of effecting metric conversion amendments. That formulation operates as a legal preference for conversion instruments over possible conflicting provisions in other written laws when the conversion power is invoked.

Good faith protection: If a proclamation is disallowed, s 5(4) preserves anything done or omitted to be done in good faith before the resolution of disallowance from being affected or invalidated. That provision protects officials and third parties who acted in reliance on a proclamation prior to disallowance.

No new substantive rights or penalties in this Act: The Act itself does not create new substantive civil rights, criminal offences, or penalties. Its powers operate to amend other instruments which may contain rights, duties or penalties; the substance of those regimes remains in the underlying instruments as amended.

Record‑keeping and publication obligations: The Act places publication obligations on the executive. Proclamations and Gazette notices must be published in the Government Gazette and tabled before Parliament within tight time windows (s 5(2)(a); s 5(3); s 6(2)). Failure to publish or table within the statutory windows would be a breach of the Act’s procedural duties, potentially exposing the resulting amendment to parliamentary disallowance or administrative challenge, although the Act does not specify a remedy beyond disallowance.

No direct penalty or enforcement scheme in the Act: The Metric Conversion Act 1972 does not itself create offences, penalties, or enforcement mechanisms for non‑compliance with converted quantities. Its operative effect is to authorise the executive to alter references in other instruments; enforcement and penalties, where applicable, remain contained in the amended primary or subordinate instruments. The Act therefore functions as an enabling vehicle rather than an enforcement statute.

Parliamentary disallowance as enforcement check: The principal statutory control over the executive conversion power is parliamentary disallowance. Section 5(4) provides that, if within the first 14 sitting days after tabling a House passes a resolution disallowing the proclamation, the proclamation ceases to have effect. Section 6(2) applies the same disallowance mechanism to statutory instrument notices. This yields a political and procedural enforcement mechanism rather than a criminal or civil sanction. The Act preserves actions taken in good faith before disallowance so that disallowance does not retrospectively invalidate prior lawful conduct under the proclamation (s 5(4)).

Administrative remedies and judicial review: The text of the Act does not specify judicial remedies or a statutory cause of action for challenging the exercise of the conversion powers. The Act’s terms, however, do not displace common law remedies that may be available for review of executive action, but the Act itself is silent on judicial review. The Act’s "notwithstanding" phrasing (s 5(1); s 6(1)) gives it primacy over other written laws for the specific conversion purpose. Whether and how a court would review the Governor’s or Minister’s exercise of the opinion threshold in s 5(1) or the Minister’s "consideration" in s 7(2) is not addressed in the statute text. The compilation materials and notes in the reprint do not record litigation or judicial interpretation of these provisions.

Operational enforcement: Agencies that administer the underlying Acts and instruments will be responsible for enforcing regulatory requirements as amended. Practical enforcement actions , issuing licences, measuring and inspecting goods, prosecuting breaches of measurement requirements , remain matters for the agencies and the substantive law in each instrument. The Metric Conversion Act does not add enforcement powers to those agencies.

Good faith protection against retrospective cancellation: Section 5(4) protects persons who acted in good faith under a proclamation from retrospective invalidation when Parliament disallows the proclamation later. This is a statutory safeguard limiting the retroactive enforcement impact of disallowance.

No express financial penalties for non‑publication or failure to table: The Act does not create criminal or financial penalties for failure by the Minister or Governor to perform the tabling or publication duties. The primary sanction provided is parliamentary disallowance and political accountability.

Notwithstanding operating clause: Sections 5(1) and 6(1) both begin with "Notwithstanding the provisions of any other Act or law", which expresses an express statutory primacy for metric conversion exercises. When the Governor or Minister invokes these powers for the specified purpose, the conversion instrument overrides conflicting provisions in other written laws to the extent necessary for the substitution of metric references (s 5(1); s 6(1)). That does not abolish the underlying law but alters its numeric references as substituted by the proclamation, notice or regulation.

Cross‑reference to Commonwealth declarations: The definition of "metric system of measurement" in s 3(c) includes units declared by the Commonwealth Metric Conversion Act 1970 or any Act of the Commonwealth in substitution for that Act. The compilation notes identify that the Commonwealth Metric Conversion Act 1970 has been repealed by the Weights and Measures (National Standards) Amendment Act 1984 (Note 3). The practical effect is that Commonwealth determinations about recognised units, and later national standards legislation, were anticipated to feed into the range of units available for substitution under the State Act. Practitioners must therefore consider the Commonwealth statutory and regulatory framework for definitions of metric units when identifying permissible substitutions under this Act.

Effect on primary and subordinate instruments: The Act expressly authorises amendments to three categories of written law: (1) references in Acts by Governor’s proclamation (s 5), (2) references in statutory instruments by Ministerial notice with Governor approval (s 6), and (3) subsidiary legislation by regulations made by the Governor on the Minister’s recommendation (s 7). The statutory definition of "statutory instrument" is broad (s 3) and includes proclamations, Orders in Council, regulations, local laws, by‑laws, notices, and orders, so the Act interacts with both state and local laws. The Act’s powers therefore operate across the body of State written law subject to the procedural rules it prescribes.

Interaction with legislative processes: The Act changes the normal mechanism for amending Acts and subordinate instruments by enabling executive instruments to substitute metric references without enactment of specific primary legislation for each change. Parliament retains an oversight role by disallowance after tabling (s 5(3)-(4); s 6(2)), but it loses the default pre‑legislative scrutiny for each specific unit conversion. Thus the Act interacts with the standard legislative separation of roles by delegating conversion work to the executive with prescribed parliamentary review windows.

Temporal interaction: Proclamations and notices must not take effect earlier than Gazette publication (s 5(2)(a)). That timing rule interacts with any timing provisions in the underlying Act or instrument. Where an Act sets effective dates keyed to particular non‑metric measures, the conversion instrument can be drafted to take effect on specified days but not earlier than publication. The Act therefore constrains when converted references can become operative relative to other statutory timing mechanisms.

Limit on scope of changes: Section 7(2) creates an interactional constraint on regulation‑making power: a Minister recommendation for amending subsidiary legislation may only be made where the Minister considers each proposed amendment is solely for metric substitution. That prevents the regulation pathway being used to bundle metric conversion with other policy or substantive changes to subsidiary legislation, at least on the face of the Act. This interacts with the federal/state rulemaking practice by effectively reserving mixed substantive changes in subsidiary legislation to other regulation processes.

Omitted or spent provisions: The reprint notes state that s 4 and the First to Fourth Schedules are omitted as spent under the Reprints Act 1984 (Notes). Those omitted provisions historically set out particular amendments. Practitioners should note that prior amendments effected by those schedules are completed and the schedules are removed for current reprints. The compilation table lists amendment Acts and commencement dates which show how the Act evolved (Compilation table).

No express displacement of contractual law: The Act authorises substitution of quantities in public law instruments. It does not state how substituted statutory quantities affect private contracts or common law rights that refer to former statutory measures. Interaction between the converted statutory references and private law instruments will be determined by ordinary principles of statutory interpretation and contract law; the Act itself does not prescribe a specific rule on that point.

Legislative amendments recorded in the compilation: The reprint includes a compilation table listing the original Act (Metric Conversion Act 1972, No. 94 of 1972; assented 4 December 1972; commenced 4 December 1972) and subsequent amending Acts with dates of assent and commencement. Amendments recorded in the compilation table include: Metric Conversion Act Amendment Act 1973 (No. 19 of 1973), Amendment Act (No. 2) 1973 (No. 83 of 1973), Metric Conversion Act Amendment Act 1975 (No. 42 of 1975), Local Government (Consequential Amendments) Act 1996 s 4 (No. 14 of 1996), and Statutes (Repeals and Miscellaneous Amendments) Act 2009 s 91 (No. 8 of 2009). The compilation table also records Reprint 1 as at 11 September 2009, which incorporates the listed amendments.

Notable changes: Section 3 was amended by No. 14 of 1996 s 4 (as stated immediately following s 3). Section 7 (power to amend subsidiary legislation) was inserted by the Statutes (Repeals and Miscellaneous Amendments) Act 2009 s 91 (see the note that s 7 was inserted No. 8 of 2009 s. 91). Section 4 of the original Act is omitted in the current reprint under the Reprints Act 1984 s 7(4)(e); the First to Fourth Schedules are similarly omitted as spent (Notes).

Omitted and spent provisions: The reprint notes state that provisions and schedules that effected specified amendments have been omitted because they are spent. Practitioners should consult the compilation table for the historical context of those amendments and the reprint date for the current operative text (Reprint 1: as at 11 Sep 2009). The statutory text within the reprint carries notes indicating where omissions have been made under the Reprints Act 1984 (see the note after s 4 and the note after s 7).

Commencement details: The original Act commenced on the day it received Royal Assent subject to s 4(2) (s 2). The compilation table includes commencement particulars for the amendment Acts; for example, the Local Government (Consequential Amendments) Act 1996 amendment to s 3 commenced on 1 July 1996 (see compilation table).

Cross‑jurisdictional developments: The definition in s 3(c) contemplates units declared under the Commonwealth Metric Conversion Act 1970, but the reprint notes that the Commonwealth Act has been repealed by the Weights and Measures (National Standards) Amendment Act 1984 (Note 3). This indicates that Commonwealth legislative change altered the federal metric legal landscape after the State Act’s enactment; the State Act’s definition preserves the mechanism to pick up units declared by Commonwealth law as it evolves.

No post‑2009 amendments recorded in the reprint: The reprint reflects amendments up to the Statutes (Repeals and Miscellaneous Amendments) Act 2009. The text does not record further amendments beyond those listed in the compilation table and the reprint date (11 September 2009). Users relying on the Act for current practice should check for later amendments beyond the reprint date.

Drafting history signals: The text shows the legislature’s intent to provide an expedited administrative pathway for metric conversion through multiple instruments, and subsequent amendment has extended that pathway to subsidiary legislation (s 7 insertion 2009). The compilation table shows periodic legislative activity in the 1970s and later adjustments to align with local government and statutory housekeeping amendments.

No cases or judicial decisions are recorded in the Act text or the compilation notes. The reprint does not list any litigation history, judicial commentary or reported decisions construing the Metric Conversion Act 1972. The Act itself does not include references to case law or indicate any judicial interpretation of its provisions.

Absent judicial authorities in the source: Because the statute text and compilation notes supplied contain no litigation citations, the source does not provide any precedent on how courts have treated the Governor’s opinion threshold in s 5(1), the extent of the "notwithstanding" formulation, the application of the ±10% tolerance (s 5(2)(b); s 7(3)), or the procedural requirements for tabling and disallowance. The Act does not record instances where proclamations, notices or regulations made under it were disallowed by Parliament, nor does it report any challenges to such instruments.

Practical consequence for practitioners: The absence of litigation history in the statute text means that statutory operation, particularly the scope of executive discretion and the interplay with parliamentary disallowance, appears to have been designed as a primarily administrative and political process. Practitioners seeking to understand how courts might approach judicial review of exercises of power under this Act must rely on general administrative law principles and any external case law not present in the reprint. The supplied source offers no guidance on the thresholds or standards courts would apply.

Statutory protections relevant to litigation: The Act contains a provision preserving good‑faith actions (s 5(4)) so that disallowance does not invalidate anything done or omitted to be done in good faith before disallowance. This has potential litigation significance in that it creates a statutory bar to retrospective invalidation in such circumstances; however, there is no reported decision in the source applying or interpreting that provision.

Recommendation: The source contains no litigation history. Users who require judicial authorities on the Act’s operation must search court databases or consolidated legislative histories beyond the text supplied here.

Numeric tolerance allows small but consequential drift: The Act permits substituted metric quantities that are not exact conversions, provided the new quantity is within ±10% of the original (s 5(2)(b); s 7(3)). That tolerance may be operationally significant where statutory thresholds determine legal obligations, entitlements or offences. A converted threshold that is up to 10% different from the numerical equivalent of the previous measure can change the set of persons or goods captured by a rule. The statute permits this variance expressly; it does not require the substituted metric quantity to be the exact mathematical conversion. Practitioners must therefore scrutinise converted thresholds to see whether small percentage differences produce material legal effects.

Timing and effective date constraint: A proclamation may only take effect on or after the date specified, but not earlier than the date of Government Gazette publication (s 5(2)(a)). That means an executive instrument cannot lawfully backdate conversions to a day prior to Gazette publication. Implementation plans and compliance communications must accommodate the Gazette publication timing.

Short parliamentary windows for oversight: The Minister must table a copy of a proclamation within the first six sitting days after Gazette publication (s 5(3)). Parliament then has a further 14 sitting‑day window in which a resolution of disallowance may be moved (s 5(4)). These are short timeframes. If Parliament does not act within the prescribed sitting days, the conversion instrument remains operative. Practitioners should take care to track Gazette publication and tabling dates because the disallowance right attaches to those windows.

Good faith insulation limits retrospective invalidation but not forward effect: Section 5(4) states that disallowance does not affect or invalidate anything done or omitted to be done in good faith before the passing of the disallowing resolution. That protects reliance on the conversion up to the point of disallowance. However, disallowance ceases the instrument’s effect from that point forward, potentially changing ongoing compliance obligations. Stakeholders should not assume permanence of a conversion until the disallowance windows have expired.

"Notwithstanding" language broad but purpose‑limited: Sections 5(1) and 6(1) operate notwithstanding other Acts or laws. While this language is broad, it is expressly constrained to achieving the stated purpose: the substitution of references to metric units for non‑metric physical quantities. The Act does not authorise other substantive policy changes by conversion instruments. Section 7(2) emphasises this constraint for subsidiary legislation by requiring Ministerial consideration that the amendments are solely for metric substitution. Practitioners should beware of attempts to bundle unrelated policy changes with metric conversion instruments; the Act restricts such bundling on its face.

Definition relies on external declarations: The metric system definition includes units declared under Commonwealth law (s 3(c)) and references units approved by the General Conference on Weights and Measures (s 3(a)). The compilation notes record that the Commonwealth Metric Conversion Act 1970 has been repealed (Notes), which means the State definition relies on other Commonwealth or international declarations as they evolve. That external dependency can affect which units are available to be used in substitution and may require administrators to monitor Commonwealth and international developments.

Broad definition of statutory instruments: The term "statutory instrument" in s 3 is broad and includes local laws, by‑laws and notices. That breadth means many subordinate instruments are within the scope of the s 6 notice power. Local government instruments can therefore be amended under the mechanism provided, which may catch parties by surprise if they do not expect executive conversion of local by‑laws.

No express transitional rules for private contracts: The Act does not address how conversions affect private contracts that reference statutory measures. For example, if a licence fee or exempt quantity is defined by statute and that statutory quantity is altered within ±10%, the Act does not state how that affects private agreements reliant on the former measure. This gap requires careful legal analysis in each case, and parties should seek advice when statutory reference changes are made.

Potential for inconsistent conversions across instruments: Because the Act allows multiple executive instruments (proclamations, notices, regulations) to convert references across Acts and subordinate laws, there is potential for non‑uniformity if conversions are not centrally co‑ordinated. The Act does not impose a statutory requirement for harmonised conversion tables, nor does it prescribe where to publish consolidated lists of conversions. Administrations should therefore ensure central coordination to avoid inconsistent unit substitutions across the regulatory landscape.

Record of amendments and spent schedules: Section 4 and the First to Fourth Schedules are omitted as spent (Notes). That means earlier, perhaps detailed, conversion steps have been completed and are no longer part of the operative text. Practitioners relying on historical operation must be careful to consult compilation materials and the Gazette archives for the precise language of past substitutions because the reprint omits spent schedules.

No penalty for non‑action: The Act does not provide a penalty where the Governor or Minister fails to effect conversions. If a conversion is required but not implemented, the statute has no self‑executing enforcement mechanism compelling action. The source does not indicate an administrative remedy for non‑performance of conversion duties.

Administrators preparing a conversion instrument

• Confirm scope and authority: Identify whether the change concerns an Act (use s 5), a statutory instrument (use s 6) or subsidiary legislation (use s 7). Check that the proposed amendment is limited to substituting a non‑metric reference by a metric reference for the purpose of giving proper effect to the Act’s purposes (s 5(1); s 7(2)).

• Apply the numeric tolerance: Ensure the substituted metric quantity is within ±10% of the original physical quantity (s 5(2)(b); s 7(3)). Document the rationale and conversion calculation showing the substituted figure falls within the statutory tolerance.

• Satisfy the opinion/consideration threshold: For proclamations under s 5, the Governor must be "of opinion" conversion is necessary or expedient to give proper effect to an Act’s purposes (s 5(1)). For regulations under s 7, the Minister must consider the amendments are solely for metric substitution (s 7(2)). Record the basis for these conclusions in administrative files even if the statute does not prescribe a reasons publication requirement. A contemporaneous record assists in responding to parliamentary questions or scrutiny.

Publication and tabling steps

• Gazette publication: Draft the proclamation, notice or regulation and publish it in the Government Gazette. Do not set the effective date earlier than the day of Gazette publication (s 5(2)(a)).

• Table in Parliament: After Gazette publication, ensure a copy is laid on the Table of each House within the first six sitting days of the House following publication (s 5(3)). For instruments made under s 6, s 6(2) applies the same tabling requirement.

• Monitor disallowance windows: Track the sitting‑day timeline for the 14 sitting days after tabling during which either House may move a resolution disallowing the instrument (s 5(4); s 6(2) applying s 5(4)). If disallowance is a risk, plan transitional arrangements to manage the possibility that the instrument could cease to have effect from the passing of a disallowance resolution.

Stakeholder communication and implementation

• Notify affected parties: Provide clear public guidance and direct notices to regulated entities, local governments, licensing bodies and industry groups explaining the change, the effective date, and whether the substituted quantity differs from exact metric conversion. Explain the ±10% tolerance and whether it affects thresholds, fees or licences.

• Update forms and registers: Amend regulatory forms, licence conditions, fees schedules, compliance checklists, signage and measurement instructions to reflect converted units. Ensure linked information systems and compliance software use the substituted metric figures.

• Coordinate centrally: Maintain a central register or conversion matrix of all substitutions effected under the Act, with citations to the relevant proclamation, Gazette notice or regulation and the date of Gazette publication and tabling. This reduces the risk of inconsistent conversions across agencies and instruments.

Legal and contract issues

• Assess contract and rights impact: Where private contracts, licences or statutory entitlements refer to statutory quantities, evaluate whether the substituted metric reference alters contractual obligations or entitlements. Consider whether transitional fidelity or express modification is needed for legal certainty.

• Consider transitional wording: Although the Act does not supply transitional provisions for private law effects, regulators may include transitional administrative guidance or amendment clauses in the instrument where permissible to reduce ambiguity about the effect on ongoing licences or enforcement actions.

Record‑keeping and audit trail

• Maintain contemporaneous decision records: Keep internal records documenting the opinion or consideration required by s 5(1) and s 7(2), the conversion arithmetic showing compliance with the ±10% limit, and reasons for any selection of metric units where multiple options exist. These records support accountability and respond to parliamentary scrutiny or judicial review.

• Ensure good faith protections are respected: If a proclamation or notice is later disallowed, remember actions taken in good faith before disallowance are preserved by s 5(4). When implementing, ensure that enforcement and licensing actions taken before any possible disallowance are documented as being in good faith.

Monitoring and intergovernmental alignment

• Watch Commonwealth and international standards: Because s 3 links the metric system definition to Commonwealth declarations and units approved by the General Conference on Weights and Measures, monitor Commonwealth weights and measures legislation and international standards to ensure conversions conform to the recognised list of metric units (s 3(a)-(c)).

• Coordinate with local governments: Because the statutory instrument definition includes local laws and by‑laws (s 3), coordinate with local governments and councils to align conversions where local instruments are affected.

Practical drafting tips

• State the margin of error used: When drafting conversion instruments, specify whether the substituted figure is the exact mathematical equivalent or a rounded figure within the ±10% tolerance and document why that rounding was chosen.

• Use clear cross references: Amend the phrasing in the affected instrument to make clear which previous non‑metric reference is being replaced and include a citation to the proclamation, Gazette notice or regulation effecting the substitution.

• Provide an explanatory schedule: Include an explanatory schedule in the instrument cross‑referencing the original non‑metric wording and the substituted metric wording to assist courts, regulators and the public in tracing the change.

In summary, compliance requires careful procedural handling of publication and tabling timelines, accurate numeric substitution within statutory tolerances, clear stakeholder communications, and central coordination to avoid inconsistent conversions and legal uncertainty. The Act gives administrators power to effect substitutions, but it imposes discrete procedural and numeric limits that must be respected and documented.