Marine 5™ Brochure
Explore NDIR CO2 technical specifications
Explore the NDIR CO2 technical specifications, pumped capabilities, and sensor configurations.
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Contents
Despite decades of safety protocols, the continued loss of life in enclosed spaces remains the maritime industry’s most persistent tragedy. Investigations repeatedly reveal that the failure to identify hazards systematically is rarely a lack of effort, but rather a lack of precision.
While SOLAS Regulation III/19 has long mandated enclosed space entry and rescue drills, and SOLAS XI-1/7 requires ships to carry portable gas detectors, the industry has historically relied on the recommendations of Resolution A.1050(27). That era has ended. To address persistent safety gaps, the IMO has adopted Resolution MSC.581(110). Endorsed on 3 December 2025, this resolution officially revokes A.1050(27). For Shipowners and Masters, this is not a simple paperwork update—it is a high-priority safety mandate that bridges the gap between basic SOLAS requirements and modern technical reality.
The most significant technical change is the elevation of Carbon Dioxide (CO2) to a mandatory pre-entry testing parameter. Under the old regime, standard 4-gas monitors (O2, LEL, CO, H2S) were the industry norm.
With MSC.581(110) now in full effect, standard 4-gas monitors are no longer the industry benchmark. If you are carrying cargo that depletes oxygen or emits toxins, you are now expected to monitor CO2 at the ppm level.
The Operational Reality: Standard percent range sensors often lack the resolution to measure the 5,000 ppm limit for CO2 accurately. Non-Dispersive Infrared (NDIR) technology is now the benchmark for compliance; it identifies lethal CO2 concentrations that standard electrochemical sensors miss. Unlike traditional sensors, NDIR provides the stability and high-resolution ppm (parts per million) monitoring essential for these new limits, ensuring the crew is alerted to the invisible threat of CO2 long before it becomes fatal.
The new regulations draw specific attention to a hazard often overlooked in standard risk assessments: the oxygen-depleting properties of iron in damp environments. As highlighted in the regulation’s technical appendices, the simple process of oxidation (rusting) in a confined, damp space can rapidly consume oxygen and elevate CO2 levels.
The Operational Reality: A space does not need to contain “dangerous” cargo to become lethal. Whether it is the ship’s internal structure or a cargo of scrap metal, moisture and bare steel can create an asphyxiation hazard in a matter of days. MSC.581(110) requires that these “passive” chemical changes are now strictly accounted for during the pre-entry assessment.
Hazards do not respect bulkheads – physical boundaries do not guarantee atmospheric safety. MSC.581(110) expands the definitions of “Connected” and “Adjacent” spaces to prevent gas migration accidents.
Any area linked by doors or trunks. A manual door, even if watertight, must be treated as a connection because it is impossible to verify an airtight seal from the outside.
These share a common boundary with the area that could contain a hazardous atmosphere. Precautions must now specifically relate to the potential failure of that common boundary (e.g., bulkhead corrosion or seal failure).
Both of these areas should be treated as hazardous until proven otherwise.
The Operational Reality: Do not assume one ventilation strategy fits all. Paragraph 4.3 of the resolution warns that ventilation in an adjacent space may differ significantly from that in the source space, requiring a unique risk assessment for each entry.
Procedural “hard rules” have been tightened to eliminate human error:
Vessels must now maintain a ship-specific Enclosed Space Register both on board and ashore. This is a dynamic tool, not a static list, designed to synthesise physical hazards with atmospheric risks. Furthermore, MSC.581(110) introduces the requirement for a dedicated Enclosed Space Emergency Response Plan. This is no longer just a “drill” requirement under SOLAS III/19; it is a documented, ship-specific strategy that the Master must verify before issuing any entry permit.
The Operational Reality: A primary example of a space requiring focus is the “Australian Ladder.” These are notoriously difficult to ventilate; under the new rules, they require unique locking arrangements and must be specifically accounted for in the Emergency Response Plan to prevent accidental entry or botched rescue attempts.
Compliance now demands drills at least once every two months. These must move beyond simple muster and include the practical use of atmospheric testing instruments and resuscitation techniques.
The Operational Reality: More than half of enclosed space fatalities are would-be rescuers. The new era of safety demands a rigid, methodical adherence to the ship-specific Emergency Response Plan. Unplanned rescue attempts are strictly prohibited under the new framework.
If you are not sure where your fleet stands, start with these three actions:
Navigating the intersection of SOLAS and MSC.581(110) can be complex. At Martek, we provide more than just hardware; we provide certainty. Our NDIR-equipped Marine 5 technology is designed to meet the high-resolution demands of the new resolution, helping you build a tailored roadmap to total fleet safety.