Dear All,

I found below statments from Drager gas detection hand book , however a bit confused becuse alot of gas testers in market such as BW has PVC tube referes as Tygon tubing as probe , so based on below statments their probe is not suitable for detecting H2S gas..any body has experience of that ? the below statments is correct or just marketing stuff?

"A rubber hose is not suitable for measuring hydrogen sulphide – the material lets the H2S molecules diffuse to the outside"

Thank you in advance

SHV

Doesn't fully answer your question but this recent safey bulletin from HSE explains why hose selection is critical.

https://www.hse.gov.uk/safetybulletins/failure-to-detect-dangerous-gas.htm

SHV

Not my area of expertise so you are probably right. The bulletin refers to "pumped gas detectors" and says "sampling tubes are sometimes used to extend the reach of the detection device and/or to allow detection at an increased distance from the user." The problem was "adsorption of the flammable vapour on the surface of the sample tube before it could reach the gas detector."

I have probably misinterpreted this, or maybe you have additional information about the case.