Pipe Materials

This data should be helpful for the detector groups to select plastic tubing materials for the chamber gas connections. The table quotes general properties, depending on the suppliers or the exact composition of materials a specific behavior can be different. In particular the gas compatibility data give only an indication, critical parameters must be crossed checked by the users.

Many plastic materials burn at fairly low temperatures and can emit toxic smoke. Some plastics (like PVC) are forbidden at CERN, others are only tolerated in small quantities, so check safety issues with the GLIMOS of your experiment and with TIS.

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(comment 1)
POLYURETHANE PUR much softer than rilsan tubing blue (Angst+Pfister type) 7.01 - 13.88 * 10-10 (air)perhaps high for H2O (comment 2) bad effects with C2H2F4 under radiation, tube becomes brittle and brakes! (comment 4) medium
POLYAMIDE RILSAN (NYLON) PA11 rigid; kinks easily if bent transparent milky oxygen 4.0*10-10 water 4'300*10-10 water absorption 1.1% (comment 3) quite good; probably ok even for DME medium
POLYTETRA- FLUORETHYLENE PTFE rigid transparent opaque water absorption < 0.01% CF4 or C2H2F4 may be absorbed and cause slight swelling; possibly bad with DME(comment 5) very poor
TEFLON (PERFLUOR - ETHYLEN - PROPYLEN) FEP very rigid transparent water absorption < 0.01% possibly less absorbent to halogenated gases than poor, slightly better than PTFE
POLYETHER - ETHERKETONE PEEK rigid originally brown water absorption < 0.05% very good; crystalline type is ok for DME, no attack through freons (comment 6) good
UNISIL-W SILICON PRESSURE TUBE SI-RU reinforced tubing, but fairly flexible transparent opaque ? can be bad good
TYGON (GRADE 3370) SI-RU reinforced tubing, but fairly flexible transparent  ? can be bad < 200 kgy
POLYURETHANE PUR burns badly, propagate flame, black smoke okay for non-aggressive gases, better than rilsan for safety low Angst+Pfister AP 12 0115 0604(comment 7)
POLYAMIDE RILSAN (NYLON) PA11 burns and drops (only small quantities allowed) good chemical resistance, medium for safety low CERN store SCEM 38.40.30.
POLYTETRA - FLUORETHYLENE PTFE highly toxic and corrosive smoke (to be avoided in large quantities) only small quantities for specific purpose medium CERN store SCEM 38.86.10
TEFLON (PERFLUOR - ETHYLEN - PROPYLEN) FEP highly toxic and corrosive smoke (to be avoided in large quantities) only small quantities for specific purpose medium Angst+Pfister AP 12 0201 0604
POLYETHER ETHERKETONE PEEK very good fire retardants low smoke emitter good very high  
UNISIL-W SILICON PRESSURE TUBE SI-RU good okay for auxiliaries, but can di-polymerize not for chamber gases low Angst+Pfister 06.5331.7004-13
TYGON (GRADE 3370) SI-RU good okay for auxiliaries, but can di-polymerize not for chamber gases ? norton performance plastics


  1. At room temp: cm3(stp) cm-2mm-1 s-1(cm hg)-1 (take me back)
  2. From air liquid depends on polymer composition (take me back)
  3. Oxygen diffusion behaves like a classical leak: doubling the flow results in half the oxygen. Water diffusion is high and largely independent of the gas flow. Possibly saturation due to water desorption from the polyimide material. Data from R.C.A.. Brown et al. DELPHI 84-8 gas-1 (take me back)
  4. Bad behaviour with RPC gas under radiation tests. (take me back)
  5. A few gases may give problems with PTFE or Teflon, for instance fluorine, CLF3, F2O,etc. (take me back)
  6. DME resistance depends on hardening process, some types are good.crystalline:
    • Solid who have regular or symmetric molecular (crystalline) structure.
    • Amorphous: any noncrystalline solid in which the atoms and molecules are not organized in a definite lattice pattern. (for instance: glass, plastic, gel, etc.)
    • Solids who have irregular (non-aligned) molecular structure (take me back)
  7. Called flexion PUR. (take me back)