Tetraethyl orthosilicate or Tetraethoxysilane or TEOS (Si(OC2H5)4)


CAS nr.



Measuring ranges

Standard range 30ppm


TLV level (TLV-TWA)



Relative density (compared to air):




  • TEOS is mainly used as a crosslinking agent in silicone polymers and as a precursor to silicon dioxide in the semiconductor industry
  • TEOS is also used as the silica source for synthesis of some zeolites
  • It is also used in the coatings for carpets


Are you looking for a gas detection solution for Tetraethyl orthosilicate?

New Cosmos offers a variety of Tetraethyl orthosilicate gas detectors such as the SH-4001WAD/TEOS detector which does not respond to IPA. Very often IPA is a source of false alarms on TEOS detectors. New Cosmos-BIE has developed a special detector which can see the difference between TEOS and IPA. False alarmas in you clean room belong to the past when using this detector.


Associated products: