Providing the skills, approved training , technical resources and scuba regulator spare parts information for those wishing to qualify and work as technicians in the dive industry.
Servicing Scuba Equipment: An introduction
All equipment used by divers underwater or in the provision of their breathing gases is fundamentally life support equipment. Scuba regulators and compressors work at extremely high pressures and use innovative engineering design techniques to function correctly.
The repair, adjustment and testing of this equipment is not intuitive even for the mechanically minded or those with formal engineering training in other disciplines. The Service information, custom spare parts and special custom tools are usually difficult if not impossible to obtain outside the trade.
Only formal training in the repair and maintenance of dive equipment such as that received during the ASSET approved Dive Industry Technicians Course (DITC) can ensure the continuing safe and reliable operation of life support equipment.
Servicing SCUBA regulators
A laypersons attempt at repairing a SCUBA regulator usually results in the destruction of the item, or worse still, the creation of a botched unreliable repair that seems to work OK on the bench yet later fails underwater after just a few uses, killing the diver. Since the fool who botched the regulator repair is usually killed in the incident, his grieving relatives encouraged by contingency fee lawyers, normally commence legal action against anyone even remotely involved with the incident who has a ‘pot of gold’ large enough to make it worth their while to sue and win…. Often the usual victims of this predatory legal action are either the scuba regulator manufacturer (‘the favorite’), the dive shop who sold the spare parts kit, or any other dive professionals remotely connected to the dead divers regulator by way of ‘touching it’ in any way prior to the incident.
To discourage unauthorized botched repairs by laymen, the Information, parts, and custom tools available from this web site are only made available to formally trained service technicians. It is my opinion after years of contact with the different scuba equipment manufacturers, especially Scubapro, US Divers, Aqualung, APEKS and Poseidon, that they really do care about the safe reliable performance of their product and work continuously through their appointed service engineers to achieve this goal. In accordance with many countries legal systems, they are behaving in a wholly responsible and legally defendable manner by not assisting fools to kill themselves.
The Dive Industry Technician Training Course is the only approved training available to provide broad based ‘hands-on’ experience in servicing regulators from all the worlds major manufacturers of dive equipment.
Experienced, formally qualified Divers Life Support Equipment technicians may apply for a Username & password to access the regulator repair section by Contacting ScubaEngineer.com
Inspecting Scuba tanks
The standard American DOT 3AL 3000 aluminium scuba tank manufactured by the Luxfer and Catalina companies, represents an amazing piece of metallurgical technology. The single piece seamless construction manufacturing technique, plus subsequent heat treatment results in a structure containing 20 times more strength than the original aluminium billet from which it was made. Rough handling, miss-use, corrosion and many other factors can critically effect the strength and integrity of its construction. The end result is an explosion, that usually occurs during refilling, killing the compressor operator and destroying the dive shop.
Further opportunity for death and destruction occurs during scuba tank inspection, when untrained technicians try to remove the pillar valve without testing that the tank is truly un-pressurized. In 2003, a dive instructor working at Koh Tao, Thailand suffered a critical injury when a scuba tank pillar valve plus the removal tool was jettisoned through his leg during a servicing action; the aluminium tank went through a few concrete walls before flying through the air a hundred yards to crash into a tourist’s beach bungalow. Thankfully no one else was injured. A well trained army medic conveniently located close to the original explosion quickly put a tourniquet on the injured guys leg saving his life.
Even for those Dive Operators attempting a visual inspection, few realize that an aluminium tank is susceptible to Sustained Load Cracking or SLC cracks in the neck area, nor do they carry out thread gauging, or understand what ‘Eddy Current’ NDT testing is.
Further confusion exists in the scuba industry, in that the hydrostatic test is somehow believed to be the usual way a dodgy scuba tank is identified and removed from service. The paradox is that scuba tanks rarely fail hydrostatic test and It is the visual inspection where most scuba tanks are identified as having critical defects and are condemned or otherwise removed from service.
The mysteries of the hieroglyphics on US DOT tanks SP6498, 7042, 3AA, 3AL (or lack of a 3AL ?), let alone the myriad of standards BS5045,EN1964, EN1965, HOAL 1,2,3,4 previously used by countries now within the EEC, and it’s implications for the unskilled cylinder inspector, remain a mystery only to be revealed during an accident investigation.
Further, few ‘visual inspectors’ certified by the recreational and technical training agencies actually bother to purchase the expensive Compressed Gas Association CGA pamphlets that contain the standards against which the tanks (cylinders!) are tested to.
Steel tanks are also not without their own problems as anyone who has been near the sea with ferrous materials will testify.
If there is one truth in the world it is ‘that rust never sleeps’ A flooded steel scuba tank lying on its side can exhibit corrosion accelerated by the high pressure of air in the tank, that can lead to critical weakening of the cylinder wall sufficient to cause an explosion within a few months.
Comprehensive training in Scuba tank inspection such as the ASSET approved courses below, saves lives.
- Cylinder Testing Course – Pt 1 (Practices and Procedures)
- Cylinder Testing Course – Pt 2 (Metallurgy, Inspection and Determination)
- Composite Cylinder Inspection Training Pt3
Includes a full revision of both US-DOT, European, Australian and British Inspection standards
Using Compressors and Air Banks
It looks just like an engine, so anyone whose tried tinkering with a car or motorbike engine has a go fixing it. When a car engine breaks down, the car drifts to a halt and usually no one gets hurt. If a compressor repair is incorrectly carried out, or the operator fails to carry out routine periodic checks of oil, filter condition and air purity, or even just situates a compressor against a wall in an inadequately ventilated small room… all hell can break use, ranging from pumping air with deadly levels of carbon monoxide, exploding and killing the operator, or just lazily pumping moist air into the owners scuba tanks causing internal corrosion that will cost him a few thousand US$ replacing the dangerously corroded cylinders the next they get a proper visual inspection.
All attempts at using ‘second source’ or ‘gray manufactured’ substitute compressor spare parts or filter materials to save costs also meet with similar failure or unreliable performance.
Many larger operators use air banks made of 50 litre internal volume ‘J-Bottles’ converted from old medical Oxygen bottles, ignoring or unaware that many of these tanks should not be used above 140 bar/2000 psi. Just don’t be in the same street when these abused air bank tanks explode. A lethal blast radius of 10m/30ft would be a conservative estimation!
The only safe, cost effective and legally defensible use of a compressor air bank systems or Nitrox / Trimix gas blending panels is though the formal practical training of all key personnel involved in operation of the filling system.
It even saves the dive shop owner money in the long run.