O-rings are used in many Quantachrome instruments as gas and vacuum-tight seals and valves have polymeric sealing surfaces. O-rings and valves are available in a variety of elastomeric materials and these differ in their compatibilities with different gases and vapors. Listed below are the O-ring and valve materials we most commonly employ and their relative ratings[1] for use with some common fluids.
S = suitable, Ss = suitable for short exposure (<48 hours)
N = not suitable, do not use.
Fluids which are deemed compatible, at least for short periods, with all elastomers listed are highlighted in bold.
| Fluid Name | Formula | Buna-N | EPDM | Viton | Kalrez |
| Acetone | C3H6O | N | S | N | S |
| Acetylene | C2H2 | S | S | S | S |
| Ammonia (dry) | NH3 | S | S | N | S |
| Argon | Ar | S | S | S | S |
| Benzene | C6H6 | N | N | S | S |
| Butane | C4H10 | S | N | S | S |
| Carbon dioxide | CO2 | S | S | S | S |
| Carbon monoxide | CO | S | S | S | S |
| Cyclohexane | C6H12 | S | N | S | S |
| Ethane | C2H6 | S | N | S | S |
| Ethanol | C2H5OH | Ss | S | S | S |
| Helium | He | S | S | S | S |
| Hexane | C6H14 | S | N | S | S |
| Hydrogen | H2 | S | S | S | S |
| Isopropanol | C3H7OH | S | S | S | S |
| Krypton | Kr | S | S | S | S |
| Methane | CH4 | S | N | S | S |
| Nitric oxide | NO | N | N | N | Ss |
| Nitrogen | N2 | S | S | S | S |
| Nitrogen dioxide/tetroxide | NO2 (N2O4) | N | N | N | Ss |
| Nitrous oxide | N2O | S | S | S | S |
| Pyridine | C5H5N | N | S | N | S |
| Sulfur dioxide (dry) | SO2 | N | S | Ss | S |
| Sulfur hexafluoride | SF6 | S | S | S | S |
| Xylene | C8H10 | N | N | S | S |
| Water | H2O | S | S | S | S |
[1] This information has been compiled from the following sources: Cole-Parmer Parker Seal Group (O-ring Division), and Marco Rubber. This information refers to chemical compatibility only and does not imply suitability for use according to any other criteria.
If you do not see the fluid-elastomer pair of interest, please visit one of the following sites to determine suitability:
www.coleparmer.com/Chemical-Resistance
http://divapps.parker.com/divapps/seal/mobile/FluidCompatibility/Desktop/
www.marcorubber.com/compatibility.htm
If you are unsure regarding what O-rings and valve types are used in your particular Quantachrome instrument or whether a fluid not listed here can be reasonably employed, please contact Quantachrome by filling out this contact form, emailing qc.support@quantachrome.com or calling our toll-free number 1-800-989-2476.
Always involve your health and safety management when using compressed gases, refer to the appropriate MSDS available from your gas supplier (not Quantachrome) and observe all safety precautions printed in the instrument operator's manual.
Quantachrome makes no express or implied warranties or guarantees regarding the information above. Quantachrome cannot be responsible for conditions of use of any gases and shall not be liable for any injury, damage or loss resulting from the use of any of the listed materials above.
