Compressed Gas Cylinder Outlet Connections

For Reference Information Only

In these tables you will find the most common compressed gas cylinder outlet connections used with the gases and gas mixtures. The tables refer to the standards implemented in different countries, sometimes the with small variations. The DIN standard is used in most European countries. The tables are listed for various countries. This information is supplied for reference only and connectors are not available for sale.

Connection Threads:

Right handed, external thread is the normal thread and does not have an additional annotation.
Left handed thread has the LH annotation.
Internal thread has the INT annotation.

USA & Canada – CGA
Argentina – IRAM 2539
Australia and New Zealand – AS 2473.2
Brazil – ABNT
France – AFNOR
Germany (and most European countries) - DIN 477
Italy - UNI
Netherlands - NEN 3268
Spain – ITC EP6
UK - BS 341

	USA & Canada - CGA

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
CGA 110	0.3125 - 32 UNEF INT	All Gases	Small Cylinders
CGA 170	9/16" - 18 UNF INT	Argon, Helium	Non Corrosive, Small Cylinders
CGA 180	5/8" - 18 UNF INT	All Gases	Small Cylinders
CGA 240	3/8" - 18 NPT	Ammonia	Toxic
CGA 296	0.803" - 14 UNS INT	Oxygen Mix > 23%	Oxidizing Mixtures
CGA 300	0.825" - 14 NGO	Ethyl Chloride	Refrigerant
CGA 320	0.825" - 14 NGO	Carbon Dioxide	Non Flammable
CGA 326	0.825" - 14 NGO	Air	Oxidizer
CGA 330	0.825" - 14 NGO LH	Hydrogen Chloride	Toxic
CGA 346	0.825" - 14 NGO	Air	Oxidizer
CGA 350	0.825" - 14 NGO LH	Hydrogen, Methane	Flammable
CGA 510	0.825" - 14 NGO LH INT	Propane	Flammable
CGA 540	0.903" - 14 NGO	Oxygen	Oxidizer
CGA 580	0.965" - 14 NGO INT	Argon, Nitrogen	Inerts
CGA 590	0.965" - 14 NGO LM INT	Air	Oxidizer
CGA 660	1.030" - 14 NGO	Hydrogen Sulphide	Toxic
CGA 679	1.030" - 14 NGO LH	Nitrogen	High Pressure
CGA 705	1.125" - 14 UNS	Ammonia	Toxic

Argentina - IRAM 2539

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
IRAM 2539 No. 1	3/4" BSP x 1/14" - INT	Acetylene	Flammable
IRAM 2539 No. 2	W 21.8 - 1 1/4	Oxygen, Sulphur Hexafluoride	Various
IRAM 2539 No. 3	5/8" BSP - INT	Argon, Nitrogen	Non Flammable
IRAM 2539 No. 4	W 21.8 - 1/4	Ethane, Hydrogen	Flammable
IRAM 2539 No. 5	3/8" BSP - INT	Nitrous Oxide	Oxidizer

Australia and New Zealand – AS 2473.2

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
Type 10	G 5/8" RH INT	Argon, Helium, Oxygen =< 20,000 kPa	Non Flammable
Type 11	G 5/8" RH INT Extended nipple	Oxygen >20,000 kPa, =< 25,000 kPa	Oxidizer
Type 20	G 5/8" LH INT	Acetylene, Hydrogen, Ethylene, Methane	Flammable
Type 21	0.885" - 14 NGO LH INT	LPG, Propane	Flammable
Type 30	0.860" - 14 BSW RH EXT	Carbon Dioxide, Nitrous Oxide	Non Flammable / Oxidizer
Type 31	G 5/8"	Sulphur Hexafluoride, Phosgene, Methyl Bromide	Chemical Gases
Type 32	G 1/2"	Ammonia, Sulphur Dioxide	Toxic
Type 33	G 1/4"	Small cyls <4.5l water capacity	Non Toxic, Non Flammable Mixtures
Type 34	G 3/4"	R134a	Refrigerant
Type 40	G 5/8" LH EXT	Ethylene Oxide	Toxic
Type 41	G 3/8" BSP LH EXT	LPG, Propane	Flammable
Type 42	G 1/2" LH EXT	Methylamine	Toxic
Type 43	0.825" - 14 NGO LH EXT	Hydrogen Chloride, Hydrogen Sulphide	Toxic / Corrosive
Type 44	G 3/8" BSP	Calibration gas mixtures	Toxic, Non Flammable Mixtures
Type 50	24x2 Whit	Nitrogen =<20,000 kPa	Inert
Type 51	1.045" - 14 NGO RH INT	Nitrogen >20,000 kPa	Inert
Type 60	27x2 Whit	Air =<20,000 kPa	Non Flammable
Type 61	0.825" - 14 NGO	Air >20,000 kPa	Non Flammable

Brazil – ABNT

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
ABNT 172-1	3/8" -18 NGT INT	Ammonia	Toxic
ABNT 218-1	W 21.8 x 1/14" INT	Air, Oxygen, Oxygen Mix >20%	Oxidizer
ABNT 218-2	W 21.8 x 1/14" LH INT	Hydrogen, Methane	Flammable
ABNT 225-2	0.885" - 14 NGO LH	Acetylene, Butane	Flammable
ABNT 245-1	0.960" - 14 NGO	Argon, Helium, Nitrogen	Inerts
ABNT 245-1	0.960" - 14 NGO	Inert gases + Oxygen Mix <20%	Inerts
ABNT 245-2	0.960" - 14 NGO LH	Sulphur Hexafluoride	Non Flammable
ABNT 262-1	1.035" - 14 NGO INT	Sulphur Dioxide, Chlorine	Toxic
ABNT 209-1	0.830" - 14 NGO INT	Carbon Dioxide	Non Flammable
ABNT 209-2	0.830" - 14 NGO LH INT (Round Nipple)	Carbon Monoxide, Phosphine, Silane	Toxic, Flammable
ABNT 209-4	0.830" - 14 NGO LH INT (Flat Nipple)	Hydrogen Chloride, Hydrogen Sulphide	Toxic
ABNT 166-1	G 3/8" A - ISO 228-1	Nitrous Oxide	Oxidizer

France – AFNOR

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
NF B	W 30 x 1.75	Industrial Air	Oxidizer
NF C	SI 21.7 x 1.814	Argon, Helium, Nitrogen	Inert Gases
NF E	SI 21.7 x 1.814 LH	Hydrogen, Hydrogen Mix >4%	Flammable
NF F	SI 22.94 x 1.814 INT	Oxygen	Oxidizer
NF G	SI 26 x 1.5 INT	Nitrous Oxide	Oxidizer
NF H	W 22.91 x 1.814 LH INT	Acetylene	Flammable
NF J	W 25.4 x 3.175	Chlorine	Corrosive
NF K	W 27 x 2	Hydrogen Chloride	Corrosive
NF L	W 27 x 2	Inert gases + Oxygen Mix > 21%	Oxidizer
NF M	W 30 x 2	Inert gases + Oxygen Mix > 21% & CO2 < 7%	Oxidizer
NF P	W 27 x 2	Nitric Oxide, Nitrogen Dioxide	Oxidizer or Corrosive

Germany (and most European countries) - DIN 477

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
DIN 477 No. 1	W 21.8 x 1/14" LH	Hydrogen, Propane	Flammable
DIN 477 No. 2	W 21.8" x 1/14" LH	Propane	Flammable
DIN 477 No. 3	Yoke	Acetylene	Flammable
DIN 477 No. 3.1	M 24 x 2" LH	Acetylene	Flammable
DIN 477 No. 5	W 1" x 1/8" LH	Carbon Monoxide	Toxic
DIN 477 No. 6	W 21.8 x 1/14"	Argon, Helium, Carbon Dioxide	Various
DIN 477 No. 7	G 5/8"	Sulphur Dioxide	Toxic
DIN 477 No. 8	W 1" x 1/8"	Boron Trichloride	Toxic
DIN 477 No. 9	G 3/4"	Oxygen	Oxidizer
DIN 477 No. 10	W 24.32 x 1/14" RH	Nitrogen	Inerts
DIN 477 No. 11	G 3/8"	Nitrous Oxide (>3 l size)	Oxidizer
DIN 477 No. 12	G 3/4" INT	Nitrous Oxide (<3 l size)	Oxidizer
DIN 477 No. 13	G 5/8" INT	Air	Non Flammable
DIN 477 No. 14	M 19 x 1.5 LH	Mixtures	Various

Italy - UNI

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
UNI 4405	W 20 x 1/14" LH	Hydrogen	Flammable
UNI 4406	W 21.7 x 1/14"	Carbon Dioxide, Oxygen	Non Flammable / Oxidizer
UNI 4407	W 30 x 1/14"	Ammonia	Toxic
UNI 4408	W 1" x 1/8"	Chlorine	Toxic
UNI 4409	W 21.7 x 1/14"	Nitrogen	Inert
UNI 4410	W 30 x 1/14"	Air	Non Flammable
UNI 4411	W 22.9 x 1/14"	Acetylene	Flammable
UNI 4412	W 24.5 x 1/14"	Argon, Helium	Inerts
UNI 9097	G 3/8" EXT	Nitrous Oxide	Oxidizer

Netherlands - NEN 3268

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
LU 0	M 19 x 1.5 LH	Flammable Mixtures	Flammable Mixtures
LU 1	W 21.8 - 1/14" LH	Hydrogen, Methane	Flammable
LU 4	W 25.4 x 3.175" LH	Hydrogen Cyanide	Toxic
RI 2	G 22.91 x 1.814" RH	Oxygen	Oxidizer
RU 1	W 21.8 - 1/14"	Ammonia, Carbon Dioxide	Refigerants
RU 3	W 24.32 - 1/14"	Argon, Helium, Nitrogen	Inerts
RU 4	W 25.4 x 3.175" RH	Chlorine, Hydrogen Chloride, Sulphur Dioxide	Toxic
RU 6	W 28.81 x 1.814" RH	Air	Oxidizer

Spain – ITC EP6

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
TIPO B	M 30 x 1.75	Air	Non Flammable
TIPO C	W 21.7 x 1/14"	Argon, Helium, Nitrogen	Inerts
TIPO E	W 21.7 x 1/14" LH	Hydrogen, Methane, Propane	Flammable
TIPO F	G 5/8" INT	Oxygen	Oxidizer
TIPO G	M 26 x 1.5 INT	Oxygen Mix > 23%	Oxidizing Mixtures
TIPO H	G 5/8" LH INT	Acetylene	Flammable
TIPO J	W 1"	Hydrogen Chloride, Hydrogen Bromide	Toxic and Corrosive
TIPO M	M 19 x 1.5 LH	Calibration Gas Mixtures	Mixtures
TIPO T	W 31.75 x 1/7" 237	Chlorine Drum Tanks	Toxic or Corrosive
TIPO U	G 3/8"	Nitrous Oxide	Oxidizer

UK - BS 341

Connector Type	Connector Thread	Gas or Gas Mixture	Remarks
BS 341 No. 2	G 5/8" LH	Acetylene	Flammable
BS 341 No. 3	G 5/8" INT	Air, Argon, Neon, Nitrogen	Inerts
BS 341 No. 3	G 5/8" INT	Oxygen	Oxidizer
BS 341 No. 4	G 5/8" LH INT	Acetylene, Hydrogen	Flammable
BS 341 No. 4	G 5/8" LH INT	Carbon Monoxide, Methane, Natural Gas	Flammable
BS 341 No. 6	G 5/8"	Chlorine, Hydrogen Chloride	Toxic
BS 341 No. 7	G 5/8" LH	Flammable Refrigerants	Flammable Refrigerants
BS 341 No. 8	W 0.860" x 14 TPI	Carbon Dioxide	Non Flammable
BS 341 No. 10	G 1/2"	Ammonia	Toxic
BS 341 No. 12	G 1/2"	Sulphur Dioxide	Toxic
BS 341 No. 13	W 11/16" - 20 TPI	Nitrous Oxide	Oxidizer
BS 341 No. 14	G 3/8"	Hydrogen Cyanide, Nitric Oxide	Toxic
BS 341 No. 15	G 3/8" LH	Carbonyl Sulphide, Hydrogen Sulphide	Toxic