gas bottle
A gas cylinder is a pressure vessel for the transportation and storage of under high pressure related gases and vapors . Pressure vessels with a smaller volume (often for single-use use) are called gas cartridges , and even smaller ones are called gas capsules .
Gas cylinders can have a volume of up to 150 liters , with a nominal pressure of up to 300 bar . Such gas cylinders are primarily filled with gases whose critical point is well below the ambient temperature of 20 ° C and which therefore cannot be liquefied. Important exceptions to this are bottles with carbon dioxide , acetylene and liquid gas in which gases are liquefied or dissolved in liquid.
Material for container construction
Depending on the intended use and gas content, gas cylinders of different materials are used. Highly pure gases are preferably transported in gas cylinders made of aluminum or stainless steel , gases for industrial use predominantly in gas cylinders made of tempered steel .
For use as a breathing apparatus in the rescue service, as a propellant gas tank, for example in automobiles, and for use in flight and rocket technology , more and more gas cylinders made of comparatively light fiber composite materials are gaining ground . The inner layer of such composite or composite gas cylinders forms a thin-walled barrier layer (English liner: inner liner ). Materials such as steel , stainless steel, aluminum or plastic are used for the barrier layer ; it ensures the tightness of the bottle and accommodates the bottle valve. The static strength of the bottle against the internal pressure (mostly 300 bar operating pressure) is achieved by wrapping the sealing layer with carbon , aramid or glass fibers under pretension and fixing the resulting outer layer, for example with epoxy resin . Higher wall thicknesses of the barrier layer have better static properties and are therefore only wrapped cylindrically , lighter bottles can be achieved through thinner barrier layer wall thicknesses and a crossed winding over shoulder and foot, the lightest - for example for space travel - are - statically optimal - spherical.
From 50 liter / 200 bar cylinders it can be seen that with increasing tensile strength of the steel (from about 750 to 990 N / mm² and more) the mass typically decreases from 67 kg to just under 50 kg. Breathing protection and diving cylinders made of particularly high-strength steel are known as light steel cylinders . In addition to the mass of the bottle, there is also that of the valve - mostly forged from brass , more rarely stainless steel - depending on the bottle thread size, pressure and outlet typically 300 to 600 grams. The bottles always have a connection thread in the metal neck, generally mostly conical in two different sizes. These seal the thread itself, originally with hemp , later about 0.3 mm thin lead capsules, currently wound plastic. With diving and breathing apparatus, especially with the increase in the standard pressure to 300 bar (from 1995), cylindrical threaded connections, e.g. M18 × 1.5 with an elastic O-ring seal, which can be screwed together with a much lower tightening torque , have become popular.
For the formation of the cylindrical thread of fiber composite bottles with a metal barrier layer, the bottle neck is thickened in terms of wall thickness. Also, bottles, their belly itself is made entirely without metal, typical barrier materials are then PET or HDPE , have a with the setting of the matrix to glued neck of a lightweight aluminum material, which as a corrosion protection practical anodized / anodized is. In order not to expose the fibers to the forces of turning on and unscrewing the valve, the metal necks typically have flat surfaces for engagement by a fork wrench on.
Cylindrical high-pressure bottles, on the other hand, are clamped for valve installation on the cylindrical belly over a length of about 20 cm between round or prismatic jaws with rubber pads. Thanks to sufficient material strength and rigidity, they have sufficient strength for this.
To indicate damage from scratches, blows or heat, plastic bottles can be equipped with sleeves and rubber caps and / or are painted. Covered protective covers made of fire-resistant fabric insulate against heat when used in fire fighting and offer protection against abrasion .
Pure metal bottles are painted in order to classify the contents by color and to reduce corrosion. Until around 1950, steel bottles were also used without painting. Metal bottles always have data stamped on the shoulder about manufacture, testing, nominal pressure and gas content. Thanks to its spherical curvature, the spherical shoulder has twice the pressure resistance with the same wall thickness, but is usually additionally thickened, which is why it can be hammered in with embossed letters without damage. For a long time the painting was done with nitro lacquer until water-based lacquers became common around 1995 .
Steel diving cylinders and cylinders of the emergency services are correctly galvanized under the paintwork. This corrosion protection layer made of the base zinc can be applied purely by electroplating or up to about 0.25 mm thick by spraying. A varnish protects it. To avoid rusting on the edge of the valve, the galvanizing extends a little into the thread. Salty sea water should be rinsed off.
All bottles must be checked at least every 10 years. It is usually checked visually outside and inside for damage and with a pressure test at 1.5 times the operating pressure - filled with water. After drying, the valve is checked for leaks with air. Bottles that are intended for diving had to or must be " tüvt " at shorter intervals . Plastic bottles typically every 5 years. While plastic composite bottles were previously only approved for a limited useful life of 5, 10 or 20 years, there are already bottles with the label "NLL" - non-limited life . At the moment, steel bottles that have reached 70 years of age are principally rejected. However, there are also individual types of steel which, to be on the safe side, are eliminated much earlier in order to avoid failure due to material fatigue .
Manufacturing
The manufacture of seamless high-pressure gas cylinders from steel is a technically demanding process.
Automated systems for the production of seamless hollow bodies up to a length of about 2 meters generally consist of a heating system with auxiliary and transport equipment, a combined upsetting and piercing press, an ironing press, the central manipulator and auxiliary equipment for dispensing and removing the drawn pieces.
A square steel block heated to forging temperature is preformed in the upsetting press and then given the shape of a hollow cylinder open on one side in the piercing press by backward extrusion. In a calibration process, the outer diameter and wall thickness are set very precisely and smoothly, i.e. without grooves.
The bottom can be shaped in different ways: Bottles that do not have to stand are usually curved in a hemispherical convex shape at the foot end. A 10-15 cm high standing ring can be pressed onto such spherical bottles. For this - before joining - either the bottle is tapered a little in a lower section or the standing ring is slightly expanded at the top. Around 1990, bottles with a volume of 10–50 liters were still used in Austria with relatively thin stand-up rings, which were slightly widened at the bottom at four corners to prevent rolling away while lying on a horizontal surface and at the same time had the rounded corners slightly raised to Roll over the edge “in an almost standing position. Later, indented bottle bottoms prevailed. In a variant, a rigid, thickened flat base is raised about 1 cm in order to form a standing ring only on the outermost centimeter of the radius. The other variant has a bottom curved in a sinusoidal shape in cross section . In the middle half of the bottle diameter, the bottom is curved upwards (seen from the outside: concave, similar to a glass bottle), on both outer quarters of the diameter it is significantly less downwards. The bottle then stands on the ring-shaped curvature at around 80-85% of the diameter and can - if tilted slightly - be rolled over the edge more gently than over the "sharp" edge of a standing ring.
The neck of the bottle is then drawn into the cut blank. This happens when the bottle is only clamped on one side with a horizontal axis in red heat. With continuous reheating with gas flames, rollers press the bottle cylinder from the outside and initially from the inside to taper the bottle neck. When the temperature is low, this is drilled out for the thread that the cylinder valve is to accommodate and the typical conical thread is milled.
The bottle is heated evenly to harden and quenched in water.
An aluminum alloy is processed at a correspondingly lower temperature. In particular, diving bottles made of aluminum sometimes have a rigid, thickened, largely flat bottom. Diving cylinders made of steel with a round (convex) bottom, on the other hand, require a voluminous standing ring made of rubber.
LPG bottles
LPG cylinders contain pressurized liquefied gases . Their maximum allowable pressure depends on the vapor pressure of their contents.
Gas bottles and liquefied gas bottles are closed with a special fitting to which a suitable hose or pipe can be screwed , usually in connection with a pressure reducer , for the controlled extraction of their contents . In addition, there is a safety valve in the tapping of liquid gas bottles, which limits the permissible overpressure in the bottle to around 30 bar in order to prevent bursting.
Carbon dioxide bottles
Bottles with carbon dioxide occupy a special position . To remove the liquid, there are special riser bottles that can only be operated without a pressure reducer. The riser pipe located inside enables almost complete liquid withdrawal when the bottle is upright, to generate the refrigerant dry ice or carbon dioxide snow for fire fighting .
Safe handling of gas cylinders
Gas cylinders can pose a serious risk if handled improperly. Common reasons for accidents include:
Demolition of the valve
Since the valve is the weakest point in a gas cylinder, it is essential to protect it with a valve protection cap. If a gas cylinder is damaged by the valve being torn off in such a way that its contents, which are under high pressure, suddenly escape, the gas cylinder is greatly accelerated and can break through walls. Rules of conduct for avoidance are:
- Gas cylinders should also be secured against falling over during storage and transport, for example with chains on the wall or by using special pallets.
- Always use valve protection caps , even if the bottle is only being stored or transported
- Don't throw bottles
- Only move bottles with a crane if they are on a pallet
- Do not open the valve with force (tools)
Uncontrolled leakage of gas
If the valves are not completely closed or if there are minor leaks, gas can escape from a gas cylinder. Even with a rather “harmless” gas such as nitrogen, an uncontrolled, comparatively slow leakage of the contents of the bottle can displace the oxygen required for breathing from a room and lead to suffocation. In the case of flammable gases, explosive gas mixtures can arise that are very easily ignited - for example by pressing a light switch. Depending on whether the gas has a higher or lower density than air, the risk is greatest either in basements or in attics.
Rules of conduct for avoidance are:
- Store in well-ventilated places, preferably outdoors
- Do not transport people and gas cylinders together in elevators
Fires and oxygen
Pure oxygen is a very good fire accelerator. The valves of oxygen bottles (also called "oxygen bombs") must therefore not be greased or oiled. Always use clean, oil-free tools when handling oxygen cylinders.
If pure oxygen escapes into the environment, other objects can also ignite, especially if they are oily or dusty.
Size of pressurized gas cylinders
Pressurized gas cylinders are traded in different sizes, for air gases (oxygen, nitrogen, noble gases), hydrogen , methane and the like. a. these are bottles with a volume of 10, 20, 33 or 50 liters at a pressure of 200 or 300 bar. Smaller ones are common for supplying aquariums, as propellant gas cartridges for fire extinguishers, for supplying breathing apparatus and diving breathers. Larger ones with a volume of 80 liters are sometimes used to blow fiber optic cables into laid pipes.
The volumes of breathing apparatus bottles , which are usually worn in pairs on the back, result from the standard dimensions of the backpack and the breathing times that can be achieved, which - based on various standards - also result in non-round volumes. 4/5 / 6.8 / 7.2 and 9 liters are common sizes. For extremely narrow entrances, a compressed air cylinder with a volume of around 2 liters is carried flexibly and in front of the upper body. With the circulatory breathing gas, the breathing gas is repeatedly enriched with oxygen, so it gets by with a smaller volume: Typically 3 liters, carried across the body.
The volumes of pressurized gas cylinders for compressed air diving equipment, which are used both individually and twice, are designed for the length of a dive. Lending bottles for scuba diving at vacation spots around the world are almost always aluminum or steel individual bottles with a volume of 10 or 12 liters at 200 bar, which are attached to the BC and carried on the back with the valve pointing upwards. 15-liter single bottles are occasionally available at an additional cost. Double cylinders usually consist of a pair of compressed air cylinders with a volume of 7, 8, 10 or 12 liters. For technical diving there are also double units with 2 × 18 or 2 × 20 liter volumes. In addition, if necessary, additional, loosely carried diving cylinders are added (so-called stages ), some of which provide special gas mixtures for different diving depths and the subsequent decompression .
Acetylene bottles are available with a capacity of 10, 20, 40, 50 liters. The amount of acetylene depends on the adsorber mass (mostly kieselguhr ) and the solvent (mostly acetone ).
Carbon dioxide is not traded by volume but by mass and there are bottles with a capacity of 6, 10, 20, 25 or 30 kg. Fire extinguishers for one-hand operation contain bottles for 2 kg, portable ones often 5 kg. The ratio of volume to mass is 4 l ≙ 3 kg . In gastronomy, for example, 13.4 liters is often used.
Propane is also traded by mass and there are standard filling quantities of 5, 11 and 33 kg.
For laboratory purposes and special gases, there are small gas bottles, also known as “ lecture bottles ”, with a capacity of 0.385, 1 and 2 liters.
Medical oxygen is available in bottles of 0.8, 1, 2, 3, 5 and 10 l for mobile use in the rescue service.
Norms
EN 1089
EN 1089 is a European standard that regulates the labeling of gas cylinders in a binding manner throughout the EU. The different colored and pictorial markings of gas containers in medicine and technology was perceived as an increasing risk and therefore in 1997 a uniform system was developed.
The EN is adopted in Germany as DIN EN 1089 Transportable Gas Cylinders - Gas Cylinder Identification , in Austria as ÖNORM EN 1089 of the same name and in Switzerland as SN EN 1089.
- Part 1: stamping
- Part 2: Hazard labels
- Part 3: color coding
But the changeover also harbors the risk of confusion, so a long transition period was set until 2006. For the smooth changeover, the Austrian standard ÖNORM M 7377 and ONR 112005 (updated version: March 1, 2005) for the medical sector were also created.
EN 1089-3 color coding
The color coding of the gas cylinders provides information about the danger and the content.
In addition to the various bottle connections, the new standard is particularly used to assess the risk of a bottle from a distance. It also makes it possible to avoid mix-ups.
In the transition period, all bottles have the capital letter N (for New, New, Nouveau) on the shoulder, but this signaling will still be visible (although not mandatory). Contrary to popular belief, the standard only defines the neck of the bottle, but not the color of the jacket. For this reason, bottles can have a different jacket color. In the industry, however, the following colors were agreed (not mandatory):
- Industrial gases : gray or the same as the shoulder, but not white
- Medicinal and inhalation gases : white
- Specialty and special gases: not specified
- Fire brigade breathing air cylinders are usually yellow or red
The bottle color does not replace the dangerous goods label. Every bottle must have a dangerous goods sticker, which provides binding information about the content.
The standard does not apply to fire extinguishers and gas cylinders for liquid gas (such as propane or butane and their mixtures) and pressurized gas packs. These liquid gas bottles , available with 5 kg, 11 kg or 33 kg content, are also color-coded, but with the following meaning:
- red = returnable bottle (based on a specific company ; exchange only possible in the catchment area of the corresponding delivery company.)
- gray = owner's bottle (this type of bottle can be exchanged in Germany and a few neighboring countries without any problems.)
The jacket color given in the following tables is not mandatory, but is often used. Colors in brackets are possible alternatives.
Color coding according to standard and RAL
Color designations according to the standard in the RAL color system :
| Color sample | EN 1089-3 | RAL number | RAL name |
|---|---|---|---|
| yellow | 1018 | Zinc yellow | |
| red | 3000 | Fire red | |
| Light Blue | 5012 | Light blue | |
| Luminous green | 6018 | Yellow-green | |
| Maroon | 3009 | Oxide red | |
| White | 9010 | Pure white | |
| blue | 5010 | Gentian blue | |
| Dark green | 6001 | Emerald green | |
| black | 9005 | Jet black | |
| Gray | 7037 | Dusty gray | |
| brown | 8008 | Olive brown |
For bottles without special labeling
see also table " for industrial use "
| danger | Old marking | New labeling | Examples |
|---|---|---|---|
| Toxic and / or corrosive | Gray | Shoulder: yellow | Ammonia, chlorine, fluorine , carbon monoxide , nitrogen oxide , sulfur dioxide |
| Flammable | Gray | Shoulder: red | Hydrogen, methane , ethylene , forming gas, nitrogen-hydrogen mixture |
| Oxidizing | Gray | Shoulder: blue | Oxygen, nitrous oxide mixtures |
| Suffocating | Gray | Shoulder: Bright green | Krypton , xenon , neon |
For industrial use
| gas | Old marking | New labeling |
|---|---|---|
| Oxygen , technical (O 2 ) | blue | Shoulder: white, coat: blue (gray) |
| Acetylene (C 2 H 2 ) | yellow black) | Shoulder: maroon, coat: maroon (black, yellow) |
| Argon (Ar) | Gray | Shoulder: dark green, coat: gray |
| Nitrogen (N 2 ) | dark green | Shoulder: black, coat: gray (green) |
| Carbon dioxide (CO 2 ) | Gray | Shoulder: gray, coat: gray |
| Helium (He) | Gray | Shoulder: brown, coat: gray |
| Hydrogen (H 2 ) | red | Shoulder: red, coat: red |
| Noble gases Xe , Kr , Ne | grey black) | Shoulder: bright green, coat: gray (bright green) |
| Forming gas (N 2 / H 2 ) | red | Shoulder: red, coat: gray |
| Argon / carbon dioxide (Ar / CO 2 ) | Gray | Shoulder: bright green, coat: gray |
| Compressed air (N 2 / O 2 ) | Gray | Shoulder: bright green, coat: gray |
| Ammonia (NH 3 ) | Gray | Shoulder: yellow, coat: gray |
| Sulfur dioxide (SO 2 ) | Gray | Shoulder: yellow, coat: gray |
| Chlorine gas (Cl 2 ) | Gray | Shoulder: yellow, coat: gray |
For medical use and for inhalation
| gas | Old marking | New labeling |
|---|---|---|
| Oxygen, medical (O 2 ) | Shoulder: white, coat: blue | Shoulder: white, coat: white |
| Laughing gas (N 2 O) | gray (white) | Shoulder: blue, coat: white |
| Carbon dioxide (CO 2 ) | gray (white) | Shoulder: gray, coat: white |
| Compressed air (N 2 / O 2 ) | blue | Shoulder: white, black (rings or segments), coat: white |
| Helium / oxygen (He / O 2 ) | blue | Shoulder: white, brown (rings or segments), coat: white |
| Carbon dioxide / oxygen (CO 2 / O 2 ) | blue | Shoulder: white, gray (rings or segments), coat: white |
| Nitrous oxide / oxygen (N 2 O / O 2 ) | blue | Shoulder: white, blue (rings or segments), coat: white |
EN ISO 11117 (formerly EN 962)
|
DIN EN ISO 11117 |
|---|---|
| Area | pressure vessel |
| title | Gas cylinders - valve protection caps and valve protection cages - design, construction and testing |
| Latest edition | 2009-01 |
| ISO | 11117 |
According to the standard EN ISO 11117 gas cylinders - valve protection caps and valve protection cages - design, construction and testing, valves of gas cylinders have different screw connections depending on the type of gas in order to avoid mix-ups. The use of unapproved adapters and hoses is expressly prohibited in Germany. For some gases that are frequently used in the home, such as propane (see table below), valve outlet connections and other accessories with left-hand threads are required. This is to prevent that "hobbyists" unsuitable, but in the household known materials from the drinking water installation (z. B. garden hoses) use, which are provided with right-hand thread.
DIN 477
|
|
DIN 477 |
|---|---|
| Area | pressure vessel |
| title | Gas cylinder valves for cylinder test pressures up to and including 300 bar - Part 1: Valve inlet and outlet connections, Part 5: For test pressures up to max. 450 bar; Side connections |
| Latest edition | 2012-06 / 2002-04 |
| ISO |
Gas cylinder valves
| Port number | gas | description | thread |
|---|---|---|---|
| 1 | other fuel gases (H 2 , propane, ...) | W 21.80 x 1/14 "LH | Left |
| 2 | Propane, butane (with spigot) | W 21.80 × 1/14 "LH (deleted, see DIN EN 15202) | Left |
| 3 | acetylene | Bracket connection (similar to INT connection ) | |
| 4th | Acetylene, propane, butane up to 1 l | G 3/8 "A LH | Left |
| 5 | Dichlorosilane, carbon monoxide, hydrogen sulfide | W 1 "LH | Left |
| 6th | Ammonia, argon, chlorodifluoromethane (R22), helium, carbon dioxide, krypton, neon, octafluorocyclobutane (RC318), octafluoropropane (R218), sulfur hexafluoride, tetrafluoromethane (R14), tifluoromethane (R23), xenon | W 21.80 × 1/14 " | |
| 7th | Sulfur dioxide | G 5/8 " | |
| 8th | Boron trichloride, boron trifluoride, hydrogen bromide, chlorine, hydrogen chloride, fluorine, nitrogen dioxide, nitrogen monoxide, nitrogen trifluoride | W 1 " | |
| 9 | Oxygen (O 2 ), test gas (with oxygen> 21%) | G 3/4 " | |
| 10 | Nitrogen (N 2 ) | W 24.32 × 1/14 " | |
| 11 | Nitrous oxide (normal connection for more than 3 l) | G 3/8 " | |
| 12 | Nitrous oxide (up to and including 3 liters volume) | G 3/4 " | Inside |
| 13 | Compressed air and breathing gas according to EN 144-2 and ISO 12209-2 | G 5/8 " | Inside |
| 14th | Test gas (with oxygen <21%) | M 19 × 1.5 LH | Left |
| 15th | Methylacetylene and propadiene, mixture, stabilized | W 21.80 x 1/14 "LH | left / inside |
| 16 | acetylene | M 24 × 2 LH | Left |
| 52 | Non-flammable and non-toxic gases (300 bar) | M 30 × 1.5 | |
| 54 | non-flammable, non-toxic and non-oxidizing gases and gas mixtures (300 bar) | W 30 × 2 (15.9 / 20.1) | |
| 55 | non-flammable, toxic and corrosive gases and gas mixtures (300 bar) | W 30 × 2 (15.2 / 20.8) | |
| 56 | Compressed air (300 bar) | W 30 × 2 (16.6 / 19.4) | |
| 57 | flammable, non-toxic gases and gas mixtures (300 bar) | W 30 x 2 (15.2 / 20.8) LH | Left |
| 58 | flammable, toxic and corrosive or non-corrosive gases and gas mixtures (300 bar) | W 30 x 2 (15.9 / 20.1) LH | Left |
| 59 | Oxygen and oxidizing, non-toxic, non-corrosive gases and gas mixtures (300 bar) | W 30 × 2 (17.3 / 18.7) | |
| 60 | oxidizing, toxic and / or corrosive gases and gas mixtures (300 bar) | W 30 × 2 (18/18) |
Source:
Thread in the bottle neck
- W 19.8 × 1/14 taper DIN 477 ISO 11363 - 17E and 25E tapered thread for connecting valves with gas cylinders - Part 1: Requirements (ISO 11363-1: 2010) - commonly: small tapered (17E)
- W 28.8 × 1/14 taper DIN 477 ISO 11363 - commonly: large conical (25E)
- W 31.3 × 1/14 keg (28E) (acetylene) DIN 477-7
- M 18 × 1.5 DIN 477
- M 25 × 2 DIN 477 - O-ring d 25 × 2.65, a conical sealing surface in the bottle neck (later standardized to be significantly different with a thicker O-ring)
Thread on the shoulder ring
- W 80 × 1/11 "right - gas cylinders, with the exception of those for breathing apparatus and diving equipment, typically have a shoulder ring pressed or shrunk onto the neck, its external thread is used to screw on the valve protection cap. This is typified up to a certain gross cylinder weight, e.g. B. 130 kg and has at least one hole of about 13 mm in diameter to allow escaping gas to easily flow off if the valve is not fully closed or defective.
Slightly smaller protective cap threads are available for:
- very small gas bottles of 1 liter volume with a small conical thread
- Gas bottles for propane
EN 144
The standard EN 144-1: 1991 has partially replaced the older standard DIN 477-6: 1983 (from 1983).
Bottle neck thread
- M 18 × 1.5 EN 144 - differs only marginally from DIN 477
- M 25 × 2 EN 144 has an O-ring d 25 × 3.55 mm - it differs significantly from the M 25 × 2 DIN 477 connection
Other standards
- EN 720 Transportable gas cylinders - gases and gas mixtures
- EN ISO 11114 Transportable gas cylinders - Compatibility of materials for gas cylinders and valves with the gases in contact
- TRG 280 Operation of pressurized gas containers
Web links
- Expert group pressurized gas containers (EG-D): Flyer on color coding according to DIN EN 1089-3. (PDF; 622 kB) (as of 2010). Industriegaseverband e. V., Berlin, April 1, 2010, accessed December 6, 2015 .
- Leaflet on the color coding of gas cylinders according to DIN EN 1089 - 3 Transportable gas cylinders - Gas cylinder marking (except for liquid gas LPG) - Part 3: Color coding ( Memento of January 12, 2007 in the Internet Archive )
- Table of contents of DIN EN ISO 11117: 2009-01 at Beuth-Verlag
- TRG 280 Operation of pressurized gas containers (PDF; 250 kB)
- Is the TRG 280 still valid?
- The TRG 280 expired on January 1, 2013 in accordance with Section 27 (4) of the Industrial Safety Ordinance.
Individual evidence
- ↑ Occupational Safety Information, 6. Pressure vessel, 6.80 Safe operation of beverage dispensing systems. (PDF; 1.3 MB) ASI 6.80. (No longer available online.) In: Regulations, ASI for download. Berufsgenossenschaft Nahrungsmittel und Gastgewerbe (BGN), Mannheim, May 6, 2015, archived from the original on December 20, 2015 ; Retrieved December 6, 2015 .
- ↑ 7 - Safe handling of gas cylinders and cylinder bundles. ( Memento from November 20, 2012 in the Internet Archive ) (PDF) asb-nordhessen.de (Safety information sheet from Linde AG )
- ↑ Facts about. Safe handling of technical gases. (PDF; 3 MB) Linde AG , Linde Gases Division, Pullach, November 8, 2011, pp. 7 and 13 , accessed on December 6, 2015 .
- ↑ Hans Killian: There is only God behind us. Sub umbra dei. A surgeon remembers. Kindler, Munich 1957; here: Licensed edition as Herder paperback (= Herder library. Volume 279). Herder, Freiburg / Basel / Vienna 1975, ISBN 3-451-01779-2 , p. 36.
- ↑ Australian safety sheet for oxygen bottles. (PDF) (No longer available online.) Archived from the original on February 19, 2011 ; Retrieved September 9, 2015 .
- ↑ Bottle sizes of medical oxygen accessed October 20, 2019.
- ↑ ON> Infos> Labeling of gases: Safety in the conversion phase , Austrian Standardization Institute - document cannot be found there (August 21, 2012)
- ↑ ris.bka.gv.at (PDF)
- ↑ Combination of valves and cylinders, diving> technology. In: seveke.de , last changed January 29, 2015, accessed on May 18, 2016.
