Expert: Reza Foudazi - 9/17/2007

Question
QUESTION: I want to seal this anesthesia chamber so the iso & oxygen don't seep out through the edges.  Can I use silicone caulk to seal up the edges or are those gases & silicone not good together.  I did find a small bead of what seems to be clear silicone caulk sealing the plexiglass to the plastic.  Thanks for any info.

ANSWER: can you give me more details about the your material and describe your objective better?
regards,

---------- FOLLOW-UP ----------

QUESTION: Hello Reza,

Sure, no problem..
My wife works at an animal hospital.  They have this anesthesia chamber thats made from what I believe to be nylon or a high density plastic & plexiglass for viewing.

 There's an inlet & an outlet to allow isoflurane & pure oxygen to flow through.  Well this box isn't sealed that great & when ever the hospital technicians or Dr's use it they can all smell, taste, feel, the gases coming out of the box.  So the hospital wants me to seal it up to limit the gases escaping.  I would use common 100% silicone rubber sealant to seal up this box.  

When I was looking closely at the box I did notice what appeared to be clear silicone being used to seal between the nylon & plexi.  I don't know if this is regular silicone or some special hospital sealant.  I'm just not sure if the 100% silicone would be affected by the isoflurane & pure oxygen used in this box.

I am also waiting to hear back from the manufacturer but figured I'd try the ask the experts while I waited.  Thanks again for your time & knowledge,  Justin

Answer
Dear Justin,
The oxygen will not affect the silicon rubber, because yu can see that 25% of air is also oxygen and we use silicon made things in this atmosphere. About isoflurane, I'm not sure because I don't know its chemical structure. But I can say to you that polymers and specially silicon rubber because of their macromolecuar structure are very resitanc against different gas, but all of them age during time so they have efficient life.
regards,
Reza