Statute Details
- Title: Merchant Shipping (Tonnage) Regulations
- Act Code: MSA1995-RG12
- Type: Subsidiary legislation (SL)
- Authorising Act: Merchant Shipping Act (Cap. 179), s 392
- International basis: International Convention on Tonnage Measurement of Ships, 1969 (“Tonnage Convention 1969”)
- Current version (per extract): Current version as at 27 Mar 2026
- Revised edition: 1990 RevEd (25 Mar 1992)
- Key amendments (from legislative history): S 333/1994; S 63/1996 (effective 02/02/1996)
- Structure: Part I (General Provisions); Part II (Determining gross and net tonnages); Schedules (including excluded spaces)
- Notable provisions (from extract): s 2 (definitions); s 3 (application); s 4 (interim scheme); s 5 (notification of alterations); s 6 (application for determination); s 7 (issue of certificate); s 9 (cancellation); s 10 (inspection); Part II ss 11–18 (measurement and calculation)
What Is This Legislation About?
The Merchant Shipping (Tonnage) Regulations set out the rules Singapore uses to determine a ship’s gross tonnage and net tonnage. In plain terms, tonnage is a standardized measurement of a ship’s size and its useful capacity. These measurements are used across maritime regulation—such as safety, manning, and regulatory thresholds—so the law’s central function is to ensure that Singapore’s tonnage determinations are consistent, auditable, and internationally comparable.
The Regulations implement the International Convention on Tonnage Measurement of Ships, 1969. That Convention was designed to harmonize how gross and net tonnages are calculated globally. Singapore’s Regulations therefore define key terms, specify which ships must be measured under the new system, and prescribe the technical method for measurement and calculation in Part II.
Practically, the Regulations also create an administrative workflow: owners apply for tonnage determination, a certifying authority issues a tonnage certificate, and the certificate can be inspected and cancelled. The Regulations further address what happens when a ship is altered—because changes to structure, capacity, or permitted passenger numbers can change tonnage and therefore require regulatory notification and re-determination.
What Are the Key Provisions?
1) Definitions and interpretive framework (s 2). The Regulations begin by defining core concepts. For example, “Certifying Authority” includes the Director of Marine and other authorised organisations. “Convention” refers to the Tonnage Convention 1969 and accepted amendments. The Regulations also define “gross tonnage” (overall size) and “net tonnage” (useful capacity), and provide technical definitions for “length” and other measurement concepts. These definitions matter because the calculation rules in Part II rely on them; disputes about tonnage often turn on how these terms are interpreted.
2) Scope and which ships must be measured (s 3). Section 3 is the gateway provision. It sets out when the Regulations apply to Singapore ships (registered or to be registered). The rules are largely threshold-based, using ship length (notably 24 metres) and whether the ship is “new” or “existing,” as well as whether substantial variations occur due to alterations or modifications.
Key practical points from s 3 include: (i) new ships of 24 metres and above fall within the Regulations; (ii) existing ships of 24 metres and above are generally brought in after specified dates, but may retain then-existing tonnages for the application of other existing regulations (subject to the exceptions); (iii) ships under 24 metres have different treatment depending on registration dates; and (iv) where an owner requests, certain existing ships may have tonnages determined under tonnage rules of other maritime nations that were acceptable to the Director prior to 6 September 1985, with restrictions on re-determination.
Section 3(3) is also important: once a Singapore ship has its gross and net tonnages determined under Part II, it must not have those tonnages re-determined unless in accordance with these Regulations. This prevents “forum shopping” or repeated recalculation outside the statutory scheme.
3) Interim scheme for certain ships (s 4). Section 4 provides an interim measurement option for certain ships during transitional periods. A Singapore ship required to have tonnages determined under Part II may, at the owner’s request, use gross tonnage determined under tonnage rules acceptable to Singapore prior to 6 September 1985—provided the keel was laid (or at a similar stage of construction) within specified date windows.
Where the interim scheme is used, the certificates or documents must show only the gross tonnage determined under the earlier rules, and must include a footnote explaining that the gross tonnage was measured under tonnage rules acceptable to Singapore prior to the coming into force of the 1969 Convention. In the case of certain partial application (for example, where only specified provisions apply), the entry is limited to a particular certificate (notably the Cargo Ship Safety Radiotelephony Certificate). This is a compliance and documentation control: it ensures regulators and counterparties can see which measurement regime was used.
4) Notification of alterations and offence for non-compliance (s 5). Section 5 addresses a common real-world issue: ships are modified over time. If a ship undergoes alterations or modifications in construction, arrangement, capacity, use of spaces, passenger numbers, or permitted draught such that it would increase gross or net tonnage, the owner (or representative) must give prior written notification to the Director. The notification must include details of the nature and extent of the alterations.
Failure to notify is an offence. The extract indicates a penalty of a fine not exceeding $2,000 on conviction. While the monetary penalty may appear modest, the regulatory consequence can be significant: failure to comply can undermine the validity of tonnage-related compliance and may trigger enforcement action or require corrective steps.
5) Application process and certification (ss 6–10, as indicated by headings and extract). Although the extract truncates the text of s 6, the headings and structure show the intended process. Owners must apply for determination of tonnages to the Certifying Authority. The Regulations then provide for the issue of a tonnage certificate (s 7) and for recognition of certificates issued by another Contracting State (s 8). There are also provisions for cancellation of certificates (s 9) and inspection (s 10).
For practitioners, the key takeaway is that tonnage is not merely a calculation exercise; it is a regulated administrative outcome. The certificate is the instrument that evidences the gross and net tonnages for regulatory purposes. Accordingly, counsel advising shipowners should focus on (i) ensuring applications are properly made to the correct authority; (ii) ensuring technical documentation supports the measurement; and (iii) managing certificate validity when alterations occur.
6) Technical determination of gross and net tonnages (Part II, ss 11–18). Part II is where the substantive measurement rules sit. Section 11 states that determination of gross and net tonnages must be in accordance with Part II. Section 12 defines terms used in Part II. Sections 13 and 14 address measurement and calculation and the calculation of volumes. Sections 15 and 16 define how gross and net tonnage are determined. Section 17 deals specifically with tonnage of segregated ballast tanks—an important category for modern ship design and environmental and operational configurations. Section 18 addresses change of net tonnage, which is relevant when a ship’s configuration changes in a way that affects net tonnage.
In addition, the Schedules (including the First Schedule and Second Schedule on excluded spaces) are critical. Excluded spaces can significantly affect the calculation of net tonnage (and sometimes gross tonnage depending on the method). For disputes, the classification of spaces as “excluded” or “included” is often determinative, so practitioners should treat the schedules as part of the operative rules, not merely background.
How Is This Legislation Structured?
The Regulations are organised into two main parts plus schedules:
Part I: General Provisions contains definitions (s 2), the scope of application (s 3), transitional/interim measurement rules (s 4), notification requirements for alterations (s 5), and the administrative steps for applying for determination and obtaining certificates (ss 6–10).
Part II: Regulations for Determining Gross and Net Tonnages sets out the technical methodology. It includes: (i) the mandatory basis for determination (s 11); (ii) definitions for Part II (s 12); (iii) measurement and calculation rules (ss 13–14); (iv) the substantive definitions and computation of gross and net tonnage (ss 15–16); (v) special rules for segregated ballast tanks (s 17); and (vi) rules dealing with changes in net tonnage (s 18).
Schedules provide additional technical detail, including excluded spaces. These schedules are essential for accurate tonnage computation and for ensuring that measurement outcomes align with the regulatory framework.
Who Does This Legislation Apply To?
The Regulations apply to Singapore ships—that is, ships registered or to be registered as Singapore ships—subject to the specific thresholds and transitional rules in s 3. The obligations primarily fall on shipowners (and their representatives), especially when applying for tonnage determination and when notifying the Director of alterations that could increase gross or net tonnage.
They also apply to certifying authorities (the Director of Marine and other authorised organisations). Certifying authorities must follow the statutory measurement and calculation rules in Part II and issue, recognise, inspect, and (where required) cancel certificates in accordance with the Regulations.
Why Is This Legislation Important?
For maritime practitioners, the Merchant Shipping (Tonnage) Regulations are important because tonnage measurements are foundational to compliance. Many regulatory regimes use gross and net tonnage as thresholds or triggers. If tonnage is wrong—or if the ship’s tonnage certificate is not properly maintained—downstream compliance can be affected, potentially leading to enforcement action, delays, or the need for corrective certification.
The Regulations also provide a structured mechanism for international consistency. By aligning with the Tonnage Convention 1969 and recognising certificates issued by other Contracting States, Singapore reduces barriers to cross-border operations and supports mutual recognition. This is particularly relevant for shipping groups with fleets trading internationally and for transactions involving ships with existing foreign tonnage certificates.
From a risk-management perspective, s 5’s notification requirement is a practical flashpoint. Alterations are common during refits, conversions, and operational changes (including changes in passenger capacity or permitted draught). Counsel should advise owners to implement internal compliance processes that track modifications and assess whether they could increase gross or net tonnage, so that prior notification to the Director is made and the tonnage certificate regime remains accurate.
Related Legislation
- Merchant Shipping Act (Cap. 179) (authorising provision: s 392)
- Merchant Shipping (Authorised Organisations) Regulations 1996 (definition of “Certifying Authority”)
- Merchant Shipping (Safety Convention) Regulations (referenced in the interim scheme)
- Merchant Shipping (Non-Convention Ships) Safety Regulations (referenced in the interim scheme)
- International Convention on Tonnage Measurement of Ships, 1969
Source Documents
This article provides an overview of the Merchant Shipping (Tonnage) Regulations for legal research and educational purposes. It does not constitute legal advice. Readers should consult the official text for authoritative provisions.