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Published on 16/02/2022

Fixed Gas Detection on Tankers

Fixed gas detectors help safeguard against a range of hazardous gases such as LPG, ammonia, butane and propane.

Gas tankers or carriers can transport a variety of hazardous substances besides oil including LPG, ammonia, butane and propane. Understanding the unique risks posed by each gas, or a combination of them, is crucial in order to preserve the health and safety of crews and ocean environments.

Once determined, mitigating and eliminating the risks posed by gases on board tankers both to crew and to the environment is vital, as mismanaged or improperly checked gas storage systems can quickly pose a deadly threat to life. Although proper management is the first crucial step towards preventing the catastrophic consequences of a gas leak or compromised inert gas system, gas detection is also vital to ensure watertight protection should an unexpected or unavoidable leak occur.

Management of gas on board tankers

Gases have a variety of applications on board ships from everyday use and medical support to cargo – but on tankers, the management of gas becomes more expansive and complex due to the vast volume of potentially hazardous substances.

Inert gas systems aim to mitigate the risks associated with gas on board tankers through spreading inert gas over oil cargo hydrocarbon, simultaneously increasing its LEL (Lower Explosion Limit) and decreasing the HEL (Higher Explosion Limit). The concentration of inert gas is then maintained at around 5%.

Inert gas systems offer a first line of defence and protection against explosions, but in a complex system of a significant size comprised of a labyrinth of pipework and components, all linking various systems within the network itself, leaks can sometimes occur.


Gases can pose a variety of significant risks when carried on board any sea-going vessel, but on tankers in particular these are amplified due to the sheer volume on board. Where a smaller vessel may have four or five oxygen cylinders on board, a tanker can carry anywhere up to 85,000m3 gas.

When stored even in the smallest quantities, gases such as butane, LPG and petroleum vapours can rapidly ignite when in contact with common substances (or each other) and cause a fire or explosion that could quickly destroy an entire vessel. Sensitive to changes in pressure and temperature, these gases are often more volatile due to their state and method of storage, especially oxygen, nitrogen and butane.

With so many gases present in one area, all with the potential to be instantly explosive should the slightest error occur, the risk to health and life is amplified. Proper management of gases on board alongside watertight gas detection systems are key in order to maintain safety and full compliance with SOLAS and MARPOL regulations.


Fixed gas detection systems work much like a fire or carbon monoxide alarm in the home, covering a set space with pre-determined parameters which enable them to sound the alarm when gas concentrations reach a certain level. But unlike detectors in a domestic setting, these sophisticated systems are specifically designed to cover large areas and must be able to immediately identify numerous different types of levels of gases in the atmosphere, in order to prevent the potentially catastrophic consequences of an otherwise unnoticed leak and preserve life. They are also designed to be calibrated and programmed to detect specific saturations of gas in any particular environment, depending on the types of gases and application.

Gas detection systems work in tandem with inert gas systems and other safety protocols to ensure that gases are being safely contained and managed at all times, providing that extra layer of security and peace of mind should anything fail.


On board any sea-going vessel, but in particular tankers, a gas detection system must be robust enough to withstand the elements, sensitive enough to detect even the smallest breach and versatile enough to cover a variety of gases. MARPOL guidelines state that sufficient numbers of gas detection units should be determined for each vessel depending on its size, as full coverage is vital due to the potential domino-effect a leak anywhere on board a tanker can have.

A fixed gas detector system is essentially the only way to protect against the dangers of gas leaks – and securing systems with robust, reliable and accurate technology is essential. 

Fixed solutions from Martek Marine

Specifically designed for use at sea, our robust gas detection solutions offer full compliance and complete peace of mind.  

MM2000 provides full protection against flammable, toxic and asphyxiant gases monitoring up to 32 sensors at any time. Easy to use with one-man calibration, MM2000 is fully SOLAS and ISGOTT compliant.

MM5001 is specifically designed for ballast tank gas sampling, providing a permanent, compact system featuring calibration-free, leading edge technology to conduct constant, reliable flammable gas analysis.

VecSafe accurately monitors inert gas oxygen and pressure levels in Vapour Emission Control Systems, preventing over or under pressurisation in line with USGC and IMO legislation.

When used alongside our portable gas detectors, our fixed gas detection systems provide comprehensive and all-encompassing safety support to protect vessels and their crews against the dangers of gas.

Learn more about Martek Marine gas detection solutions or contact our team today.