When the boating season kicks off and you dust off your lifejackets after their winter hibernation it's worth carrying out a few essential checks to make sure all is well... 

1. Firing mechanism

The firing mechanism of your lifejacket may be a manual or automatic activation type. Automatically activated lifejackets rely on a mechanism that must be replaced periodically, so it's worth opening up your jacket and just checking to see if you need to replace it. There are three types of firing unit that are commonly used, and they are dated differently. Below are details of how to check yours: 

United Moulders Cartridges

There are three main types of United Moulders cartridges for automatic life jackets, varying by age and compatibility:

  1. Mark 5 Auto Cartridge: Activates when submerged, inflating the life jacket.
  2. Pro Sensor Auto Cartridge: Fits Mark 5 life jackets, also inflates upon immersion, and features a visible status indicator that pops off when activated.
  3. Pro Sensor Elite Auto Cartridge: The latest version with a different screw thread, combining previous features with enhanced moisture resistance and reliability.

Each cartridge has a 'replace by' date and should be replaced by this date or within two years of first use, whichever comes first.

See more >

Halkey Roberts Super Bobbin

Halkey Roberts Super Bobbin Life Jacket firing mechanisms activate automatically when the bobbin dissolves in water, releasing a pin that punctures the CO2 cylinder to inflate the jacket. These units should be replaced every three years based on the manufacture date, as fitting dates are typically unavailable. 

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HAMMAR Life Jacket firing mechanisms are hydrostatic, activating when submerged in water, preventing accidental inflation due to rain or humidity.
This system has a simple green/red indicator window, as well as a 'replace by' date. If it either shows red or the replace by date has passed, it should be replaced.
Note: Hammar units are often glued to cylinders, so consider cylinder replacement regardless of firing.
See more >

Firing mechanism



2. Inflation cylinder

Your jacket's inflation cylinder is like its powerhouse, filled with compressed CO2 gas. When triggered, it swiftly discharges this gas into the jacket, inflating it to keep you safe. Now, cylinders don't have an expiration date, but it's smart to give yours a once-over. Look out for any telltale signs: if it's been fired, you'll spot a puncture mark at the tip, signaling it's time for a swap. And if you see any corrosion creeping in, definitely consider a new one.

For a double-check, give it a weigh-in. The full weight should be stamped on the cylinder's side. If it's lighter, it's time to sound the alarm. When replacing, make sure to screw it in snugly by hand. A loose cylinder won't do its job properly, or worse, not at all!

Inflation cylinder

Trade Secret:  One of the most common reasons that lifejackets don't inflate is simply because the cylinder or firing unit has become unscrewed. A simple check that this is hand tight before using your lifejacket could save your life! See more >



3. Bladder

Think of the bladder in your inflatable life jacket as its hidden buoyancy booster, storing CO2 for emergencies. Despite its strength, it can still get damaged from everyday use.

It is generally reommended that each year you should take the time to pump up your jacket to check for leaks. Then, gently deflate it using the valve at the end of the oral inflation tube and pack it away according to the manufacturer's instructions.

Try leaving your jacket inflated for 24 hours as a test, but be careful not to accidentally trigger the main firing mechanism of the life jacket whilst inflated. This could potentially damage the bladder. If you want to be extra cautious, remove the cylinder before the test.

Unfortunately, if you find a leak during inspection, it can't be fixed. It's safer to replace the jacket.



Trade Secret:  Try not to blow the bladder up with your mouth when testing, this puts moisture in to the bladder which is not good for the bladder in the long term. See more >


4. Straps/Buckles

Whilst checking our jackets it's well worth inspecting the webbing for any signs of damage, as well as the buckles and fasteners. Check the whole jacket over for any signs of stitching coming undone or tears and damage. 


Trade Secret:  A great deal of research has shown how effective crutch straps can be at saving lives. If your lifejacket is not fitted with one you can purchase these as aftermarket parts here and fit them very quickly and easily. See more >




5. Lights

Many life jackets now come with lights already fitted making them perfect for nighttime cruising, but also just improving your overall visibility in a man overboard situation.
Even if your light is within its expiry date, it's wise to turn it on occasionally to ensure it hasn't accidentally activated and drained the battery. Manual lights can be easily switched on for testing, and most automatic lights feature a manual override for this purpose.

If your jacket doesn't have a light installed, your annual check-up is the perfect opportunity to add one for added safety.


Trade Secret:  When installing a light try and think about where the light will sit with the jacket inflated - the higher the better as this should offer good visibility all round. See more >




6. Spray Hoods

There is relatively little to go wrong with spray hoods, but while the jacket is open just give them a once over, and as with lights, if you don't have one fitted, now is a great opportunity to get on installed.

life jacket spray hoods



7. Safety Lines... 

If you own or frequently use a safety line, it's essential to give it a thorough inspection.

Examine the webbing carefully, searching for any signs of damage, no matter how small. These lines endure significant forces if ever deployed, so it's crucial to avoid any potential failures. If your safety line includes an overload indicator, ensure it's still in good working condition.

Metal buckles may seize up or corrode if not properly rinsed after use; while lubrication can often remedy this, when in doubt, it's best to replace them.

life jacket safety lines
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