Education
Are All Fire Extinguishers The Same?
Published on 04 Nov 2025
Did you know that marine and fire extinguishers on land are significantly different? At first glance, they may look almost identical, you’ll see the same red cylinder, same nozzle, same pull pin. But on the inside, they’re designed very differently to meet the unique challenges of their environments.
While both serve the same purpose to stop fires quickly and safely, the key difference is the way they store pressure, discharge agents, and withstand environmental stress varies greatly. On land, extinguishers are typically built for stable, dry conditions and minimal vibration. Out at sea, however, extinguishers must perform reliably in humid, high-vibration, and corrosive marine environments, where a small design flaw can mean failure when it matters most as additional support often takes significantly longer.
In this post, we’ll break down the key differences between stored-pressure and cartridge-operated extinguishers, explain why they can’t be used interchangeably, and highlight what every ship chandler, marine engineer, and facility manager should know before making a purchase.
Stored-Pressure Extinguishers
Often in Singapore, the fire extinguishers you see in offices, shopping malls, factories, and residential buildings are almost always the stored-pressure type. These extinguishers are designed so that both the extinguishing agent and the propellant gas (usually nitrogen) are stored together inside the same cylinder. When activated, the pressurised gas forces the extinguishing agent out through the nozzle almost instantly.
This design is simple, efficient, and ideal for the stable environments found on land. It’s why stored-pressure extinguishers are the standard under the Singapore Standard SS 578:2019.
Cartridge-Operated Extinguishers
Unlike their land-based counterparts, marine fire extinguishers are often cartridge-operated, it’s design to to withstand the harsh, unpredictable conditions at sea. In these units, the propellant gas is stored separately in a sealed cartridge rather than inside the main cylinder. When activated, a small mechanism punctures the cartridge, releasing the gas into the extinguisher body and forcing the extinguishing agent out through the nozzle.
This design might seem like a small difference, but it makes a major impact on reliability and maintenance. Because the pressure isn’t constantly stored in the main cylinder, there’s less risk of slow leaks or corrosion-related pressure loss, especially in humid or environment with high salt content. This is crucial for marine and offshore applications, where constant vibration and exposure to seawater can degrade materials over time.
Cartridge-operated extinguishers also allow for easier inspection and recharging, the crew or technicians can safely open the cylinder for refilling without depressurising the entire unit if needed. This makes servicing simpler on-board vessels or offshore platforms, where equipment downtime can be costly.
It’s for these reasons that cartridge-operated models are the preferred design under marine safety standards, including those recognised by the International Maritime Organization (IMO).
Spotting the Difference
At a glance, you can tell a lot about a dry powder fire extinguisher. Land extinguishers typically have a pressure gauge and a standard painted body because their pressure is stored in the same cylinder. Marine-approved extinguishers may omit the gauge (in cartridge-operated types), display a visible gas cartridge, and show marine certification marks such as the MED Wheelmark, USCG or class society approval. They also feature heavy-duty finishes and marine-rated mounting brackets to cope with vibration, salt spray and ship movement. Recognising these signs helps ensure your extinguishers are fit for purpose and compliant with the right standard.