Testing and inspection of diving cylinders - wikipedia Testing and inspection of diving cylinders Periodical inspection and testing to revalidate fitness for service See also : Diving cylinder, Gas cylinder, and Hydrostatic test Water jacket hydrostatic test diagram Condemned diving cylinders set aside for metal recycling Transportable pressure vessels for high - pressure gases are routinely inspected and tested as part of the manufacturing process. They are generally marked as evidence of passing the tests, either individually or as part of a batch ( some tests are destructive ), and certified as meeting the standard of manufacture by the authorised testing agency, making them legal for import and sale. When a cylinder is manufactured, its specification, including manufacturer, working pressure, test pressure, date of manufacture, capacity and weight are stamped on the cylinder. Most countries require diving cylinders to be checked on a regular basis. This usually consists of an internal visual inspection and a hydrostatic test. The inspection and testing requirements for scuba cylinders may be very different from the requirements for other compressed gas containers due to the more corrosive environment in which they are used. After a cylinder passes the test, the test date, ( or the test expiry date in some countries such as Germany ), is punched into the shoulder of the cylinder for easy verification at fill time. The international standard for the stamp format is ISO 13769, Gas cylinders - Stamp marking. A hydrostatic test involves pressurising the cylinder to its test pressure ( usually 5 / 3 or 3 / 2 of the working pressure ) and measuring its volume before and after the test. A permanent increase in volume above the tolerated level means the cylinder fails the test and must be permanently removed from service. An inspection may include external and internal inspection for damage, corrosion, and correct colour and markings. The failure criteria vary according to the published standards of the relevant authority, but may include inspection for bulges, overheating, dents, gouges, electrical arc scars, pitting, line corrosion, general corrosion, cracks, thread damage, defacing of permanent markings, and colour coding. Gas filling operators may be required to check the cylinder markings and perform an external visual inspection before filling the cylinder and may refuse to fill non-standard or out - of - test cylinders. Contents 1 Intervals between inspections and tests 2 Procedures for periodic inspections and tests 2.1 Identification of cylinder and preparation for testing 2.2 Depressurisation and removal of cylinder valve 2.3 External visual inspection 2.4 Internal visual inspection 2.5 Supplementary tests 2.6 Cylinder neck inspection 2.7 Pressure test or ultrasonic examination 2.8 Inspection of valve 2.9 Final operations 2.10 Rejection and rendering cylinder unserviceable 3 Notes 4 References 4.1 Sources 5 External links Intervals between inspections and tests A cylinder is due to be inspected and tested at the first time it is to be filled after the expiry of the interval as specified by the United Nations Recommendations on the Transport of Dangerous Goods, Model Regulations, or as specified by national or international standards applicable in the region of use. In the United States, an annual visual inspection is not required by the USA DOT, though they do require a hydrostatic test every five years. The visual inspection requirement is a diving industry standard based on observations made during a review by the National Underwater Accident Data Center. In European Union countries a visual inspection is required every 2.5 years, and a hydrostatic test every five years. In Norway a hydrostatic test ( including a visual inspection ) is required 3 years after production date, then every 2 years. Legislation in Australia requires that cylinders are hydrostatically tested every twelve months. In South Africa a hydrostatic test is required every 4 years, and visual inspection every year. Eddy current testing of neck threads must be done according to the manufacturer 's recommendations. Procedures for periodic inspections and tests If a cylinder passes the listed procedures, but the condition remains doubtful, further tests can be applied to ensure that the cylinder is fit for use. Cylinders that fail the tests or inspection and can not be fixed should be rendered unserviceable after notifying the owner of the reason for failure. Identification of cylinder and preparation for testing Before starting work the cylinder must be identified from the labelling and permanent stamp markings, and the ownership and contents verified. Depressurisation and removal of cylinder valve Before internal inspection the valve must be removed after depressurising and verifying that the valve is open. Cylinders containing breathing gases do not need special precautions for discharge except that high oxygen fraction gases should not be released in an enclosed space because of the fire hazard. If the valve is blocked or stuck closed it may be necessary to release the pressure by removing the burst disc or drilling into the valve body below the valve seat. These operations require care to avoid injury. External visual inspection Before inspection the cylinder must be clean and free of loose coatings, corrosion products and other materials which may obscure the surface. Foreign materials may be removed by brushing, controlled shot - blasting, water - jet cleaning chemical cleaning or other non-destructive methods. The method used must not remove a significant amount of cylinder material, and steel cylinders may not be heated above 300 ° C. Aluminium cylinders are even more restricted in the temperatures permitted, which are specified by the manufacturer. The cylinder is inspected for dents, cracks, gouges, cuts, bulges, laminations and excessive wear, heat damage, torch or electric arc burns, and corrosion damage. The cylinder is also checked for illegible, incorrect or unauthorised permanent stamp markings, and unauthorised additions or modifications. If the cylinder exceeds the rejection criteria for these items it is unsuitable for further service and will be made permanently unserviceable. Typical rejection criteria include : ( to be added ) Internal visual inspection Unless the cylinder walls are examined by ultrasonic methods, the interior must be visually inspected using sufficient illumination to identify any damage and defects, particularly corrosion. If the inner surface is not clearly visible it should be cleaned by approved method which does not remove a significant amount of wall material. Methods allowed include shot - blasting, water jet cleaning, flailing, steam or hot water jet, rumbling and chemical cleaning. The cylinder must be internally inspected after cleaning. Typical rejection criteria include : ( to be added ) Supplementary tests When there is uncertainty whether a defect found during visual inspection meets the rejection criteria, additional tests may be applied, such as ultrasonic measurement of pitting wall thickness, or weight checks to establish total weight lost to corrosion. Hardness tests on aluminium cylinders are done on the cylindrical body and must avoid making deep impressions. Cylinder neck inspection While the valve is off, the threads of cylinder and valve must be checked to identify the thread type and condition. The threads of cylinder and valve must be of matching thread specification, clean and full form, undamaged and free of cracks, burrs and other imperfections. Tap marks are acceptable and should not be confused with cracks. Other neck surfaces will also be examined to be sure they are free from cracks. In some cases threads may be re-tapped, but if the threads are altered they must be checked with the appropriate thread gauges. Pressure test or ultrasonic examination Ultrasonic inspection may be substituted for the pressure test, which is usually a hydrostatic test and may be either a proof test or a volumetric expansion test, depending on the cylinder design specification. Test pressure is specified in the stamp markings of the cylinder. The results of a correctly performed pressure test are final. Inspection of valve Valves that are to be reused must be inspected and maintained to ensure they remain fit for service. The recommended practice for valve inspection and maintenance includes inspection, and where applicable correction of threads, cleaning of components, replacement of excessively worn and damaged parts, packing and safety devices, lubrication as applicable with approved lubricants for the gas service, checks for correct operation and sealing at intended operating pressure. Checks may be done with the valve fitted to the cylinder after inspection and testing, or before the valve is fitted. Gauging of threads may be mandatory to ensure the integrity of parallel threads. If the gauge exceeds the maximum gauge limit for taper threads, re-tapping may be considered at the discretion of the competent person. Final operations Stamp markings on an American manufacture aluminum 80 cu ft 3000 psi cylinder Stamp markings on a British manufacture aluminium 12.2 litre 232 bar cylinder The interior of the cylinder must be thoroughly dried immediately after cleaning or hydrostatic testing, and the interior inspected to ensure that there is no trace of free water or other contaminants. If the cylinder is repainted or plastic coated, the temperature must not exceed 300 ° C for steel cylinders, or the temperature specified by the manufacturer for aluminium cylinders. Before fitting the valve the thread type must be checked to ensure that a valve with matching thread specification is fitted. Fitting of valves should follow the procedures specified in ISO 13341 Transportable gas cylinders - Fitting of valves to gas cylinders. After the tests have been satisfactorily completed, a cylinder passing the test will be marked accordingly. Stamp marking will include the registered mark of the inspection facility and the date of testing ( month and year ). Records of a periodic inspection and test are made by the test station and kept available for inspection. These include : Identification of the cylinder : name of current owner ; cylinder serial number ; mass of cylinder ; name of the cylinder manufacturer ; manufacturer 's serial number ; cylinder design specification ; cylinder water capacity or size ; date of test during manufacture. Records of the tests and inspections : type of inspections and tests done ; test pressure ; date of the test ; whether the cylinder passed or failed the inspections and tests ( giving reasons for failure ) ; identification stamp mark of the test station ; identification of tester ; details of any repairs made. Rejection and rendering cylinder unserviceable If a cylinder fails inspection or testing and can not be recovered, the owner must be notified before making the empty cylinder unserviceable by crushing, burning a hole in the shoulder, irregular cutting of the neck or cylinder or bursting using a safe method. If the owner does not give permission they become legally responsible for any consequences. Notes Jump up ^ This is a European requirement. Jump up ^ This is a European requirement, a requirement of the US DOT, and a South African requirement. Jump up ^ Machining marks left by the thread cutter, particularly on taper threads, but also possible on parallel threads. References ^ Jump up to : Technical Committee ISO / TC 58, Gas cylinders, Subcommittee SC 4 ( 1 July 2002 ). `` Gas cylinders -- Stamp marking ''. ISO 13769 ( 1st ed. ). Geneva, Switzerland : International Standards Organisation. Retrieved 8 November 2016. CS1 maint : Multiple names : authors list ( link ) ^ Jump up to : South African National Standard SANS 10019 : 2008 Transportable containers for compressed, dissolved and liquefied gases - Basic design, manufacture, use and maintenance ( 6th ed. ). Pretoria, South Africa : Standards South Africa. 2008. ISBN 978 - 0 - 626 - 19228 - 0. ^ Jump up to : NOAA Diving Program ( U.S. ) ( 28 Feb 2001 ). Joiner, James T., ed. NOAA Diving Manual, Diving for Science and Technology ( 4th ed. ). Silver Spring, Maryland : National Oceanic and Atmospheric Administration, Office of Oceanic and Atmospheric Research, National Undersea Research Program. ISBN 978 - 0 - 941332 - 70 - 5. CD - ROM prepared and distributed by the National Technical Information Service ( NTIS ) in partnership with NOAA and Best Publishing Company Jump up ^ ISO 6406 2005, Section 3. Jump up ^ ISO 10461 2005, Section 3. Jump up ^ Henderson, NC ; Berry, WE ; Eiber, RJ ; Frink, DW ( 1970 ). `` Investigation of scuba cylinder corrosion, Phase 1 ''. National Underwater Accident Data Center Technical Report Number 1. University of Rhode Island. Retrieved 2011 - 09 - 24. Jump up ^ BS EN 1802 : 2002 Transportable gas cylinders. Periodic inspection and testing of seamless aluminium alloy gas cylinders. London : British Standards Institution. 25 March 2002. ISBN 0 580 39412 3. Jump up ^ Committee PVE / 3 / 7 ( 25 March 2002 ). BS EN 1968 : 2002 Transportable gas cylinders. Periodic inspection and testing of seamless steel gas cylinders. London : British Standards Institution. ISBN 0 580 39413 1. Jump up ^ Staff ( 1999 ). AS 2030.1 -- 1999 Australian Standard : The verification, filling, inspection, testing and maintenance of cylinders for storage and transport of compressed gases. Part 1 : Cylinders for compressed gases other than acetylene. Reissued incorporating Amendment No. 1 ( March 2002 ) ( Third ed. ). Sydney, New South Wales : Standards Australia International Ltd. ISBN 0 - 7337 - 2574 - 0. Jump up ^ ISO 6406 2005, Section 4. Jump up ^ ISO 10461 2005, Section 4. Jump up ^ ISO 6406 2005, Section 5. Jump up ^ ISO 10461 2005, Section 5. Jump up ^ ISO 6406 2005, Section 6. Jump up ^ ISO 10461 2005, Section 6. Jump up ^ ISO 10461 2005, Section 7.1. Jump up ^ ISO 6406 2005, Section 7.1. ^ Jump up to : ISO 10461 2005, Section 14.2. 2. Jump up ^ ISO 6406 2005, Section 7.2. Jump up ^ ISO 10461 2005, Section 7.2. Jump up ^ ISO 6406 2005, Section 8. Jump up ^ ISO 10461 2005, Section 8. Jump up ^ ISO 6406 2005, Section 9. Jump up ^ ISO 10461 2005, Section 9. Jump up ^ ISO 6406 2005, Section 10. Jump up ^ ISO 10461 2005, Section 10. Jump up ^ ISO 6406 2005, Section 11. Jump up ^ ISO 10461 2005, Section 11. Jump up ^ ISO 6406 2005, Section 12. Jump up ^ ISO 10461 2005, Section 12. Jump up ^ ISO 6406 2005, Annex F. Jump up ^ ISO 10461 2005, Annex F. Jump up ^ Staff ( 2005 ). Gas container test stations - General requirements for periodic inspection and testing of portable and transportable refillable gas containers. SANS 1825. Pretoria : Standards South Africa. Table 3. ISBN 0 - 626 - 16556 - 3. Jump up ^ ISO 6406 2005, Section 15.1. 1. Jump up ^ ISO 10461 2005, Section 14.2. 1. Jump up ^ ISO 6406 2005, Section 15.1. 2. Jump up ^ ISO 6406 2005, Section 15.2. Jump up ^ ISO 10461 2005, Section 14.3. Jump up ^ ISO 6406 2005, Section 15.4. Jump up ^ ISO 10461 2005, Section 14.5. Jump up ^ ISO 6406 2005, Section 15.7. Jump up ^ ISO 10461 2005, Section 14.8. Jump up ^ ISO 10461 2005, Section 15. CEN. EN 1089 - 2 : 2002 Transportable gas Cylinders, Part 2 - Precautionary labels Superseded by EN ISO 7225 : 2007. CEN. EN 1089 - 3 : 2004 Transportable gas Cylinders, Part 3 - Colour coding Current standard. Sources Technical Committee ISO / TC 58, Gas Cylinders, Subcommittee SC4 ( 2005 ). `` Gas cylinders - Seamless steel gas cylinders - Periodic inspection and testing '' ( PDF ). ISO 6406 : 2005 ( E ). Geneva : Onternational Standards Organisation. Retrieved 4 August 2016. CS1 maint : Uses authors parameter ( link ) Technical Committee ISO / TC 58, Gas cylinders, Subcommittee SC4 ( 2005 ). `` Gas cylinders - Seamless aluminium - alloy gas cylinders - Periodic inspection and testing ''. ISO 10461 : 2005 ( E ). Geneva : International Standards Organisation. Retrieved 5 August 2016. CS1 maint : Uses authors parameter ( link ) External links Media related to Diving cylinders at Wikimedia Commons Underwater diving Modes Freediving Saturation diving Scuba diving Snorkeling Surface - supplied diving Atmospheric pressure diving Unmanned diving Recreational diving specialities Altitude diving Cave diving Deep diving Ice diving Gas blending for scuba diving Muck diving Open - water diving Rebreather diving Sidemount diving Solo diving Technical diving Wreck diving Underwater sports Diving equipment Atmospheric diving suit Backplate and wing Breathing gas Buoyancy control device Burst disc Decompression equipment Distance line / dive reel Dive boat Dive computer Dive light Diver down flag Diver propulsion vehicle Diver 's pump Diving air compressor Diving bell Diving chamber Diving cylinder Diving helmet Diving regulator Diving shot Diving suit Diving support vessel Diving weighting system Dry suit Fins Full face diving mask Integrated Diver Display Mask Lifting bag Line marker Mask Moon pool Pony bottle Rash vest Rebreather Scuba manifold Scuba set Snoopy loop Snorkel Snuba Subsurface ( software ) Surface marker buoy Testing and inspection of diving cylinders Towboard Vintage scuba Wetsuit Applications Clearance diver Commercial offshore diving Diver training Frogman Hazmat diving Military diving units Police diving Professional diving Public safety diving Recreational diving Scientific diving Underwater archaeology Underwater photography Underwater videography Diving safety : Hazards, risks and consequences Barotrauma Civil liability in recreational diving Decompression sickness Drowning Freediving blackout Dysbaric osteonecrosis High - pressure nervous syndrome Human factors in diving safety Hypercapnia Hypothermia Hypoxia ( medical ) Investigation of diving accidents Isobaric counterdiffusion Latent hypoxia List of diving hazards and precautions List of legislation regulating underwater diving List of signs and symptoms of diving disorders Nitrogen narcosis Oxygen toxicity Scuba diving fatalities Seasickness Silt out Task loading Procedures Ascending and descending ( diving ) Boat diving Buddy breathing Buddy diving Canoe and Kayak diving Controlled buoyant lift Controlled emergency swimming ascent Decompression ( diving ) Decompression practice Dive planning Diver communications Diver navigation Diver rescue Diver trim Dive log Drift diving Emergency ascent Finning techniques Night diving Penetration diving Pyle stop Recreational diver training diver certification Diamond Reef System Rule of thirds ( diving ) Scuba gas planning Scuba skills Solo diving Surface - supplied diving skills Underwater search and recovery Underwater searches History of underwater diving History of decompression research and development History of scuba diving Researchers in underwater diving Timeline of diving technology Categories : Diving equipment Professional diving Recreational diving Underwater diving history Underwater diving procedures Underwater diving safety Commons Glossary Indexes : dive sites divers diving Outline Portal Underwater breathing apparatus Surface - supplied Bailout bottle Diver 's umbilical Diving air compressor Snuba Standard diving dress Open - circuit scuba Alternative air source Aqua - lung Bailout bottle Diving regulator Porpoise regulator Scuba set Rebreathers Carleton CDBA CDLSE Cis - Lunar Cryogenic rebreather CUMA DSEA Dolphin FROGS Halcyon PVR - BASC IDA71 Interspiro DCSC KISS LAR - 5 LAR - 6 LAR - V LARU Porpoise Ray Siebe Gorman CDBA Siva Viper Helmets and masks Diving helmet Full - face mask Related Booster pump Breathing gas Breathing performance of regulators Carbon dioxide scrubber Cascade filling system Diving air compressor Diving bell Diving cylinder Electro - galvanic oxygen sensor Gas blending Gas blending for scuba diving Hydrostatic test Nitrox production membrane method pressure - swing adsorption Oxygen compatibility Sustained load cracking Testing and inspection of diving cylinders Commons Glossary Indexes : dive sites divers diving Outline Portal Retrieved from `` https://en.wikipedia.org/w/index.php?title=Testing_and_inspection_of_diving_cylinders&oldid=835772991 '' Categories : Underwater breathing apparatus Pressure vessels Breathing gases Hidden categories : CS1 maint : Multiple names : authors list Articles with short description All articles with unsourced statements Articles with unsourced statements from November 2016 CS1 maint : Uses authors parameter Commons category without a link on Wikidata Talk Contents About Wikipedia Add links This page was last edited on 10 April 2018, at 17 : 47 ( UTC ). Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: how long is a scuba tank hydro good for
Answer: five years