Before reading this article, if you don't yet have a general understanding of regulator structure, click here for an introduction: Regulator Guide – First Stage Regulator and Regulator Guide – Second Stage Regulator.
Routine Care and Maintenance
After each dive, never use your scuba tank / cylinder to blow air into the inlet port — any saltwater that enters the first stage regulator will cause corrosion. Instead, simply wipe the dust cap dry with a clean towel and replace it.
After diving, thoroughly rinse/soak your regulator in fresh water to prevent rust on the metal components of both the internal and external systems.
There has long been debate about whether the first stage regulator should be submerged during rinsing, because the cap fitted to the first stage is a dust cap, not a waterproof cap. When you cannot confirm that the dust cap will not allow water seepage during soaking, rinsing instead of soaking is the most conservative approach. Always ensure the dust cap is properly in place when rinsing. Keep water out of the working parts of the regulator.
If fresh water does accidentally enter the first stage regulator, take the regulator to a technician who will remove the hoses, attach a scuba tank / cylinder, and blow it dry. (If the water that entered was salt water, the regulator must be fully disassembled and cleaned.)
Also, when rinsing the second stage regulator, do not press the purge button. Doing so will allow water to enter the low-pressure hose. If you accidentally press it, attach the regulator to a scuba tank / cylinder and press the purge button to expel the water from the hose.
One commonly overlooked item is the mouthpiece of the second stage regulator. A worn mouthpiece can allow water to leak into your mouth. To replace the mouthpiece, cut off the old cable tie and install a new one.
Remember — never attempt to service your first or second stage regulator yourself. You could cause it to malfunction, and doing so may also void the warranty.
Storage
Make sure both your first and second stage regulators are completely dry, then loosely coil the hoses (in a circular loop) and place them in a protective regulator bag. Avoid kinking or sharply bending the hoses, as this reduces their lifespan.
Ozone and sunlight are two of the most destructive forces acting on rubber components. To protect your rubber hoses, always store your regulator in a cool, dark location away from motors that generate ozone.
Annual Service and Maintenance
Even with today's regulator materials and manufacturing technology, there is still no such thing as a truly maintenance-free product. Regular disassembly, cleaning, rust removal, lubrication, and adjustment are all necessary to keep your regulator performing at its best. Internal contamination of a regulator can come from several sources:
Dust, oil, and rust water from inside the scuba tank / cylinder: A poorly maintained scuba tank / cylinder may already have internal corrosion, and a compressor with a poorly functioning filtration system can introduce oil and moisture into the tank. When the mixture of these three contaminants builds up inside the regulator, it will impede airflow and reduce breathing quality. In severe cases, it can cause internal components to malfunction.
Salt water: Salt water that accidentally enters through the inlet port — for example, if the cylinder valve was already contaminated with salt water and was not cleaned before the tank was swapped, or if a few drops fell in during the tank change — will be forced into the regulator's internals by high-pressure air when the cylinder valve is opened. Salt water will corrode internal components, impede airflow, and reduce breathing quality. In severe cases, it can cause internal components to malfunction.
Air: Acidic substances in air can also react chemically with metal surfaces, silicone oil, or O-rings under the high-pressure conditions inside the regulator. If a regulator that has not undergone oxygen-clean preparation is used with enriched air nitrox (EANx), its internal components may oxidize at an accelerated rate.
Maintenance Procedures
Visual inspection: Check hoses and the mouthpiece for cracks or damage — flex the hoses and fold the mouthpiece to reveal any issues. Replace immediately if any are found. Also inspect exposed metal parts for corrosion.
(The following steps must be performed by a qualified technician.)
Disassembly
Use specialized tools to fully disassemble the regulator, avoiding complete seizure of components due to corrosion. Metal components, plastic parts, and O-rings are completely separated.
Regulator disassembly tools
Cleaning
Use an ultrasonic cleaner and specialized cleaning solution to remove corrosion and oil from the internal components, and to strip away any residual silicone oil.
Cleaning the regulator
The internals of the second stage regulator also require disassembly and cleaning.
Second stage regulator
Rust Removal
Use an ultrasonic cleaner and specialized cleaning solution to remove corrosion from both the inside and outside of the hose fittings. Because the cleaning solution is acidic, all O-rings must be removed beforehand; after cleaning, apply silicone oil before reinstalling them.
Removing rust from regulator hoses
Lubrication
Apply regulator-specific silicone oil (non-toxic, oxygen-compatible, high adhesion, water-resistant, low-temperature resistant, highly lubricating, and highly sealing) to the O-rings inside the regulator. Using the wrong silicone oil will degrade the O-rings and shorten their lifespan. Manufacturers recommend replacing all O-rings and gaskets every time the regulator is disassembled. However, if replacement parts are unavailable, properly lubricating the existing O-rings — provided they are undamaged and undeformed — can still extend service life without affecting function. Conversely, any O-ring that is damaged or deformed must be replaced immediately.
Adjustment
After disassembly, lubrication, and reassembly, a gauge must be used to adjust the intermediate pressure output of the first stage regulator back to the factory default value — typically in the range of 9.0–9.8 bar, as specified by the manufacturer. In addition, the valve clearance on the second stage regulator must also be adjusted to the optimal gap.
The standard annual service interval, as recommended by most manufacturers, is once per year or every 100 scuba tanks / cylinders — but no longer than two years or 300 tanks under any circumstances. Gradual wear such as spring fatigue, silicone oil degradation, O-ring hardening, and metal corrosion are happening continuously; regular servicing helps maintain good breathing quality and ensures safer diving.
Even if a full annual service is not possible, it is still recommended that you visually inspect the hoses and inlet filter every year (corrosion on the filter may indicate that salt water has entered the internals), and have a qualified technician measure and adjust the intermediate pressure.
The regulator is a diver's most important life-support device underwater. A poorly maintained regulator can cause fatigue, shortness of breath, inadequate ventilation, headaches, and other adverse symptoms. When choosing a good regulator, basic certification standards are just the starting point — the manufacturer's reputation is also a critical reference. A reputable manufacturer will never produce a defective product and expose itself to legal liability. Beyond the initial purchase, you must also consider long-term serviceability: a regulator is not a disposable item, and any product without access to ongoing maintenance support should be removed from your shopping list.
Now that you've read through the regulator maintenance guide, you should have a much deeper understanding of how regulators work. Be sure to check out our article on the myths around regulators and water exposure!
