What certifications must a maritime gas detection system have?

A maritime gas detection system must hold type approval from a recognized classification society such as Lloyd’s Register, DNV, Bureau Veritas, or ABS, and must comply with the relevant SOLAS requirements for the vessel type and trading area. In practice, most systems also need to meet specific IEC standards for marine electrical equipment and, depending on the installation, additional flag state or port state requirements. The sections below walk through each layer of certification so you know exactly what to look for when selecting or replacing a system.

Which certification bodies approve maritime gas detection systems?

The main bodies that approve maritime gas detection systems are the major classification societies: Lloyd’s Register (LR), DNV (formerly DNV GL), Bureau Veritas (BV), American Bureau of Shipping (ABS), ClassNK, and RINA, among others. These organizations issue type approval certificates confirming that a system meets the technical standards required for installation on board a classed vessel. Flag state administrations may also issue approvals, but in practice they usually defer to the classification societies they recognize.

Classification societies work within the framework set by the International Maritime Organization (IMO) and develop their own rules that translate IMO resolutions into technical requirements. When a manufacturer submits a gas detection system for approval, the classification society tests it against those rules, reviews the documentation, and, if satisfied, issues a type approval certificate. That certificate is tied to a specific product configuration, so any hardware or software change typically requires re-approval.

It is worth noting that not all classification societies are equal in the eyes of every flag state. Some flag states only accept approvals from a defined list of recognized organizations (ROs). Before specifying a system, always confirm which classification society classed your vessel and whether your flag state recognizes that society’s approvals.

What does SOLAS require for gas detection on board?

SOLAS sets the baseline legal requirement for gas detection equipment on board ships. SOLAS regulation XI-1/7 requires ships to carry portable atmospheric testing instruments, including devices capable of measuring oxygen levels, flammable gas concentrations, and toxic gases before crew enter enclosed spaces. For fixed gas detection systems, SOLAS references specific chapters depending on vessel type and cargo, particularly for tankers, bulk carriers, and passenger ships.

For tankers, SOLAS Chapter II-2 requires fixed hydrocarbon gas detection systems in pump rooms, cofferdams, and other spaces where flammable vapors may accumulate. For enclosed space entry across all vessel types, the requirements have been significantly strengthened by IMO Resolution MSC 581(110), endorsed in December 2025, which supersedes the older Resolution A.1050(27). This resolution now mandates testing for four specific gases: oxygen (O2), flammable gases, carbon monoxide (CO), and carbon dioxide (CO2). Critically, CO2 must be confirmed below 0.5% (5,000 ppm) before any enclosed space entry is permitted.

The CO2 requirement is a major shift. Traditional 4-in-1 portable detectors measuring LEL, O2, CO, and hydrogen sulfide (H2S) are no longer sufficient for full compliance. Ships now need instruments capable of detecting CO2 at the parts per million level, which requires Non-Dispersive Infrared (NDIR) sensor technology rather than the standard electrochemical sensors found in older equipment. If your portable detectors cannot measure CO2 at ppm resolution, they do not meet the current SOLAS-aligned requirements under MSC 581(110).

What is the difference between type approval and class approval?

Type approval confirms that a specific product model meets the technical standards of a classification society, while class approval means that a particular installation on a specific vessel has been accepted by the surveyor as compliant with the class rules. Type approval is issued to the manufacturer; class approval is granted to the shipowner for a specific ship.

Think of it this way: type approval is the product’s passport, proving it is eligible for use on classed vessels. Class approval is the customs stamp for a specific voyage, confirming the actual installation meets the rules for that ship’s class notation and trading area. A product with valid type approval does not automatically receive class approval; the installation design, cable routing, sensor placement, and integration with the alarm panel all need to satisfy the surveyor during inspection.

For fleet engineers, this distinction matters when sourcing replacement parts or upgrading systems. A replacement gas detector may carry valid type approval, but if it is not installed and integrated correctly, the overall system may still fail the class survey. Our service and repair support covers both the supply of approved components and the technical guidance needed to ensure the installation itself meets class requirements.

Which IEC and ISO standards apply to marine gas detectors?

The primary IEC standard for marine gas detectors is IEC 60945, which covers maritime navigation and radiocommunication equipment and systems, setting environmental and electromagnetic compatibility requirements that marine equipment must meet. For fixed gas detection specifically, IEC 60079 governs equipment intended for use in explosive atmospheres, which is directly relevant to systems installed in pump rooms, cargo holds, and other potentially flammable environments.

Beyond IEC standards, the following are commonly referenced:

IEC 61779 (series): Electrical apparatus for the detection and measurement of flammable gases
IEC 60529: Ingress protection (IP) ratings, defining how well a detector is protected against dust and water
ISO 15371: Fire suppression systems for the protection of galley cooking equipment
EN 54 (series): European fire detection standards, sometimes referenced for integrated fire and gas panels

Classification societies incorporate these IEC and ISO standards into their own rules, so a system that meets the relevant IEC standards is usually well positioned for type approval. However, the classification society’s own rules take precedence, and some societies add requirements beyond what the base IEC standard demands. Always check the specific society’s rules for the equipment category you are purchasing.

Do certifications differ for different gas types or vessel types?

Yes, certifications and requirements vary significantly depending on both the gas being detected and the type of vessel. A hydrocarbon gas detector approved for a tanker pump room must meet explosion-proof requirements under IEC 60079, while a CO2 detector for enclosed space entry on a bulk carrier follows a different technical pathway. The hazard profile of the space drives the technical standard required.

Vessel type also shapes the certification landscape:

Oil and chemical tankers require fixed flammable gas detection in cargo pump rooms, void spaces, and cofferdams, with systems certified to meet SOLAS II-2 and the relevant IGC or IBC Code requirements
LNG and LPG carriers fall under the IGC Code, which specifies gas detection requirements for cargo machinery spaces, compressor rooms, and motor rooms, often with more stringent sensor placement and alarm logic requirements
Bulk carriers and general cargo vessels face requirements primarily around portable instruments for enclosed space entry, now aligned with MSC 581(110)
Passenger ships have additional fixed detection requirements under SOLAS II-2 for machinery spaces and service areas

The gas type also matters technically. Detecting CO2 at ppm-level concentrations requires NDIR sensor technology, while detecting hydrogen sulfide (H2S) typically uses electrochemical sensors. Each sensor type has its own calibration requirements, cross-sensitivity considerations, and service intervals, all of which should be reflected in the system’s type approval documentation.

What happens when a certified gas detection system becomes obsolete?

When a certified gas detection system reaches end-of-life, the type approval certificate does not automatically expire, but the practical ability to maintain the system in a compliant state does. Once a manufacturer discontinues a product, spare parts and calibration gases become harder to source, and the system may no longer be serviceable to the standard required by the classification society. Surveyors can flag an unmaintained or non-functional system as a deficiency, regardless of whether the original approval is still technically valid.

The options when a system becomes obsolete are broadly:

Source compatible replacement parts from specialist suppliers who maintain stock of discontinued components, extending the operational life of the existing system
Retrofit a newer approved system that is compatible with the existing panel, wiring, and zone layout, minimizing the scope of work and cost
Full system replacement, which is sometimes unavoidable when the panel itself is no longer supportable

The compatibility question is particularly important for fleet engineers managing older vessels. Replacing a detector head is straightforward if the new unit uses the same protocol and connector as the original. Replacing a panel is a much larger project that can affect every detector, call point, and output device on the loop. Checking compatibility before committing to a replacement path saves significant time and cost. Our fire and gas detection solutions include a range of replacement options for discontinued systems, with technical advice on which units integrate with existing installations.

How Lavastica helps with gas detection system certification

Navigating type approvals, SOLAS requirements, and obsolete equipment is exactly where we can take work off your plate. At Lavastica, we specialize in maritime gas detection systems and keep a large stock of both current and hard-to-find components in our Rotterdam warehouse. Here is what we offer:

Type-approved systems and components from more than 100 brands, covering all major classification societies
Expert advice on compliance with current SOLAS requirements and MSC 581(110), including CO2 detection upgrades for enclosed space entry
Replacement parts and refurbished equipment for obsolete systems, extending the life of existing installations without a full replacement
Compatibility checks to confirm new detectors or panels will integrate with your current onboard setup
Fast worldwide delivery to minimize port days and get your vessel back in service quickly
Technical support and commissioning assistance to ensure the installation meets class survey requirements

Get in touch with us directly and we will find the right solution for your vessel. Learn more about who we are or contact us for a direct conversation with our technical team.

Phone: +31 (0) 10 265 5070
Email: [email protected]