Tuesday, 19 January 2016


No doubt there will be readers of this article who do not understand the meaning of a diving season, as they continue to dive straight through the year; whilst others only dive in the warmer months.  Some may be getting back into diving after a significant break.  I certainly fall into the first description, although I did go for four weeks without getting wet!  Regardless of how frequent your diving activities are, hopefully there is some information in here that you might find helpful, especially if your kit has been in the shed or garage for the last few months.  This article could also be useful for any holiday equipment that only get used once or twice a year.  In either case, it is best to find out any problems before arriving at the dive site. 

Some divers may say “it was working when I last dived it, and nothing has changed so it’ll be fine”.  That statement is probably true for divers who are diving regularly but not for those who dive less frequent.  They are the ones who use my spares box more than I do.  After all, if you were going on a long car journey, would you not check the tyre pressures and fluid levels before you set off? 

This list below is not exhaustive and I have tried to write it in a logical order, but if you are meticulous like me, a lot of these checks would have been done routinely post dive.  However, if you are starting from scratch, it is best to put at least an afternoon aside.

Firstly, I store most of my equipment pre-assembled, so I need to strip it down totally before I start.  This ensures that I do not miss anything.  And if I am checking over the wife’s equipment, she would carry out a secondary check.


Do not carry out any work if you are unsure or not qualified to do.  Diving equipment is life support equipment.  If you are in any doubt please visit your local dive shop (LDS).

Some of the points below are applicable to all cylinders whilst some are only applicable to twinsets or stage cylinders.

1.   In-date hydro/visual/O2 clean?  When was the last time that you checked your cylinder’s expiry dates?  The last thing you want after driving to the dive site to do is to miss out on a dive because of an out of date cylinder that the dive shop won’t filled.  Personally my expiry dates are stored in an electronic calendar with a reminder set one month before.  I’m fortunate to have a very good LDS; Galaxsea Divers who understands my requirements and can usually turn around my cylinders within a few days.  They will also inform me if anything may need replacing in the near future.  I will discuss LDS again later in this article.  They can often save a diving trip at the last minute, so it is important that you build a good relationship with them.

2.   Stickers.  Linked to the comments above, where are your test stickers located?  Are they scratched or damaged from being dragged inside a van or floor?  This is not a major issue for visual/hydro test dates as they are also stamped onto the cylinder, but if it is not possible to make out an O2 clean date you may not get your Nitrox or Trimix fill.  Take the cylinder to your LDS and if they were the ones that tested it they will probably replace the sticker for free.  Personally I try to keep all my stickers on the inside of the cylinder so they are protected by the wing/backplate/BCD.

3.   Threads.  Have you looked at the threads on a DIN valve?  How clean are they and do they have any crystallisation?  You may need to get out an old tooth brush and given them a clean.  Be aware that using anything too abrasive that could damage the threads.   

4.   Valves.   Is the valve easy to operate or is it stiff to turn?  You may be able to get away with adjusting the pressure on the knob by loosening the spring.  Alternatively, if you have been shown you can strip down the valve and lightly grease it.  It is a fairly simple job, but if you are unsure, again speak to your LDS. 

5.   Twinning bands.  Check the position of your twinning bands.  Have they slipped?  I don’t know how they do but they do!  I personally make the upper and lower point with of the bands with a marker but you should also double check by placing a back plate on and seeing if it fits.  You may also wish to check underneath the bands for rust.  This can easily be removed with a kitchen scourer.

6.   Stage rigging kit.  Is the rigging kit still tight?  If you use the handle, especially on the surface (not advised) the kit can ride up and make it loose.  This could cause the cylinder to hang low in the water.  Loosen the band, pull the kit tight and tighten the band back up.  Also, look at the rigging kit, especially around the band.  Has it frayed?  If so replace it by purchasing some new cord and recycle the ancillaries.  A how-to guide can be found here.  Check the inner tube or bungee for perishing and replace if required.  Finally check the bolt snaps/p clips for smoothness and oil if required.

BCD/Wing (including backplate and harness)
There is a lot to check over so I have grouped the items specifically into the wing, harness and finally backplate.  Some of the points below are also applicable to BCDs.

1.   Inflator (operation).  Check to see if it works.  Is the button sticky?  There could be some salt deposits which were missed after your last post-dive wash.  This can easily be unscrewed with the correct tool and cleaned in hot water or a sonic bath.  Replace and/or lube the o-rings if required.  After recently cleaning mine, the operation is noticeably smoother.

2.   Inflator nipple.  Is there any corrosion or salt crystals?  This can easily be cleaned off in-situ with a brush, or alternatively you could carefully unscrew it and thoroughly clean it, checking the o-ring.    Be careful on the assembly to ensure the threads are not cross threaded.  This is very easy to do on a plastic body.

3.   Hose collar.  Is the collar action smooth?  If not there could be salt deposits inside which could prevent the hose from locking on.  This will need cleaning. 

4.   (Kidney) Dump valve.  Unscrew the valve and give the rubber seal a wipe over.  Check the string is not frayed and the knot at the end is secure.

5.   Corrugated hose.  Like the rubber seal on the dump valve, I unscrew this and check its condition, as well as the cable ties on the LPI and replace if necessary.

6.   Pressure test.  Inflate the wing to see if it holds pressure.  Do this both via the low pressure hose and orally to ensure that both systems are working.  Leave it for a period of time (have a cup of tea or coffee) and check if the pressure has held.  If you have carried out the checks above, one would like to think that the leak is from the bladder.  However, it is always worth double checking, especially the o-rings and screw threads.  On a wing it is easy enough to remove the bladder from the outer but less so on some BCDs.  Submerge the inflated bladder in water and check for any leaks, no matter how small.  These can easily be fixed with Aquasure or similar.  Once completed, I put the wing back on my cylinders (not forgetting to replace your v/tail/p weight first if used).

7.   Wash the bladder.  Consider washing the bladder as it can get rid off salt crystals that can build up, and if an anti bacterial/fungal cleaner is used it can reduce the chance of a lung infection for the diver.

8.   Harness condition.  The harness will fray at some point at he point where it is threaded through the harness.  If it is too frayed replace it; new webbing can be purchased for as little at £15.

9.   Harness sizing.  This is something I do daily when diving, as my webbing is quite thin. Check your shoulder straps.  The right shoulder will become shorter over time, or at least mine does, as the light canister (battery) pulls on it.  If you have purchased a new undersuit, or have outgrown your clothes over the winter, consider re-sizing the harness (link).

10.   Corrugated hose o-ring/bungee.  My o-ring has since long gone so I use a length of 5mm bungee cord.  I do find that over time the elasticity disappears, so replace as required.

11.   Snoopy loop condition.  Similar to the inner tube loops on a stage cylinder these can perish and tear, especially the upper one which holds your backup light.  Even if it looks ok, check its size against your spares.  It may have stretched.  If so, replace it.  It is possible to get some on without re-threading your webbing. 

12.   Backplate condition.  Are there any sharp edges?  If so file these down to ensure that they do not rub a hole through your drysuit.  Do not forget the extra weight belt clip used to secure your light canister (battery).  I also ensure that my additional salt water weight is stored alongside my kit so that I don’t forget it.

13.   Suit inflation mount.  As my mount is home made (link) I tend to check around the hole where it is screwed into the backplate as it can elongate, and replace the webbing if necessary.  Finally attach the backplate to the cylinders.

Humans can swim underwater.  They cannot breathe underwater.  Therefore working regulators will save your life so should not be ignored.  Similar to BCDs/Wings (above), there is a number of areas here so I have tried to group them into general points, first stage, second stage then accessories. 

1.   In-date?  As with the cylinders, do you keep a record of when your regulators were serviced and are they still in date?  Or are you one of those divers whose mentality is “if it’s not broken don’t fix it”?  The real issue with this mentality is, if it breaks during a dive, the best case you have an OOG scenario to deal with with your buddy/team member.  However, the worst case is you have no gas supply and bolting to the surface (if you’re not inside a wreck/cave) is not an acceptable answer.

2.   Work test.  Attach your regulators to your cylinders and see if they breathe normally.  Turn the regulators off and see if they breath down and lock off.  Check if the SPG de-pressurises to zero.

3.   IP.  On the above test, consider fitting an interstage pressure gauge to a LP hose.  You will need to refer to the manufacturers guidelines to see what pressure your regulator should be set at.  Consider leaving the gauge in whilst you have dinner and see if there is creep (pressure has risen).  If so, you will need to get the regulators serviced.

4.   Second stage. Does it rattle?  Hopefully not.  Check the exhaust valve (mushroom) operates properly and does not stick.  You can check this by gently pressing on it.  If you can open the front cover (a rubber glove should work if you don’t have the correct tool), check the diaphragm is intact.  Finally, if you are able to get hold of a go/no go tool, check the settings on the purge button.  If set correctly it could reduce the chance of a free flow.

5.   Mouthpieces.  Are they fit for use?  Have they been bitten through?  I use the Apeks comfort mouthpieces which are great, but the downside is that they are really easy to bite through, especially on the left edge if the hose is pulled to the right.  Additionally with my stage regulators, as they are stored on the cylinders, the mouthpieces have distorted slightly when they’ve been kept under the hose.  I need to replace these.

6.   Hoses.  Hoses are often neglected, or at least compared to first and second stages.  If you hoses are not in good condition you could be out of gas in less than 90 seconds.  Examine each hose and look for bulges or breaks.  If you have hose protectors fitted slide them back and check underneath as any damage here can easily go unnoticed.  Personally I remove them as I find them unnecessary.  Remove your hoses to check the o-rings; make sure they’re not perished or deformed.  This could cause a pinch when re-attached to the first stage.

7.   Quick disconnects.  See hose collar under BCD/Wing.

8.   SPG.  Other than checking for needle movement, the only thing to do is to disconnect and check the o-rings on the spigot and lubricate if necessary.

9.   Boltsnaps/p-clips.  Finally check the bolt snaps/p clips for smoothness and oil if required.  Additionally, check the knot and replace if frayed; you don’t want to lost a clip under water (I’ve had my SPG come away from the D-ring underwater – true story.  I didn’t lose the clip as it was attached to my D-ring but my SPG was dangling).  A how-to guide can be found here. 

10.  Wet test.  You could leave a pressurised regulator set in the bath to check for leaks.  Finally connect the regulators to the cylinders.

Contrary to popular belief, there is actually such a thing as a dry drysuit.

1.   Suit.  Check for wear and tear.  Try placing bottles through the wrist and neck seals and then inflating the suit.  Rub down with a soapy sponge to look for leaks.  Any holes should be easily visible in the bubbles.  Also check that the inflator and dump works.  Finally, check for fit as sometimes suits and undersuits tend to shrink over the winter (or after Christmas)...

2.   Seals.  At the neck and wrist.  Are they user replaceable?  If they are not, and they look worn or are perishing, it is best to repair them now to prevent missing a dive in the future.  Consider using lubricant if not already doing so, as talcum powder dust can block the shoulder dump.

3.   Zip.  With the zip open check for visible damage to the teeth.  Check for any frayed edges.  Lubricate the zip with bee’s wax to reduce wear and tear.  On my old zip, I extended its life by waxing it after every dive.  Do it regularly. 

4.   Boots.  Check for splits and gouges in the soles. 

5.   Undersuit.  Check the condition.  Is it serviceable?  And has that shrunk over the winter too?

6.   Valves.  Check the tightness of the valves against the suit to make sure they don’t leak.  If you use talc for your seals it may be worth looking inside your shoulder dump; you would be surprised how much can get inside and clog up the dump.

7.   Hose collar.  See hose collar under BCD/Wing. 

8.   Dry gloves.  Check the o-rings and gently re-lubricate the o-rings if required.  But be careful, not too much.  You don’t want the glove to pop off underwater.

Reels and spools
1.   Line.  When was the last time you checked your line?  Consider unreeling your spools and reels, measuring the line, and re-lay the line.  Is your 30m reel still 30m?

2.   Mechanism.  Check the locking nut on any friction reels and re-lube if it’s excessively tight.

1.   General.  As mentioned on previous equipment.  Check the boltsnaps to see if they require replacing.

2.   Primary.  Are the retaining clips still working?  Check the cable, are they any nicks?  Turn the torch on (in water if required) and move the cable.  Is the light intermittent?  If so, it means that there is a break which will require fixing.  Finally, re-charge the battery.  Once done, disconnect or place in its stowage position.

3.   Backup.  As a rule of thumb a lot of these torches use the standard c cell batteries and don’t cost much.  When were they last replaced and how often have you used them?  Replace them every season and check that they still work.  It’s a backup; you’ll need them to work.  Test them and turn off.  And continue to turn off until once the head is pushed in, the torch doesn’t illuminate.  Failure to do this can mean that the water pressure will turn it on during a dive.  Re-attach onto your harness once complete.

Miscellaneous Items
1.   Fins.  Check the condition of your straps.  Have they perished or split?  The chances are that if they fail it’ll be as your kitting up, probably on a boat, without a spare set.

2.   Mask.  Is the strap in good condition?

3.   Computers/D timers.  Check the battery levels and replace if required.  If you use bungee straps, check the bungee.  Does it still retain its elasticity? 

4.   Cable/Zip ties.  If you have any of these on your equipment, take the time to replace them with spool line as they can become brittle and fail.  A how-to guide can be found here. 

5.   Knots.  Linked to above; if any look frayed or worn.  Replace them.  I can personally vouch for this, as only 2 weeks ago my primary light p-clip came away from my Goodman handle. 

6.   P-clips/boltsnaps.  Are they still smooth?  If not, oil as required.

7.   DSMBs/SMBs.  Do they still hold air?  Inflate them and leave for a few hours.  Do they still hold?  If not, check for leaks with soapy water and look at the autodump (see wing/BCD). If any take CO2 cartridges, replace them.

8.   Cutters/knifes.  Are the blades still sharp or are they rusted?  Rub off any corrosion and give a light coating of grease.

9.   Net bags.  Do you use these on a boat for your mask and fins?  Do you have one attached to a lift bag?  Check for holes.  The last thing you need is something to fall out and you lose it.

Don’t go straight into deep challenging dives.  Re-build your confidence slowly

The boring bit!
All opinions expressed in my articles are my own and may differ to other instructor’s and agency guidelines; by no means are they wrong and I would not wish to disrepute any of them.  This article is for information only and should not replace proper training.

Safe diving!

Timothy Gort
BSAC, PADI & SDI/TDI diver training
l Mob: 07968148261 l Email: tim@rectotec.co.uk l