Westlake operations producing petrochemicals and plastics have earned the prestigious ISO 9001:2000 certification. ISO certification signifies that a company has an ongoing program of continual quality improvement. The ISO 9001:2000 certification indicates that Westlake's production facilities meet rigid standards and supplier requirements.

Westlake Chemical Corporation operations with ISO 9001:2000 certification include the following:

(Click on location below to view certificate)

•  Westlake Longview

•  Westlake Vinyls, Inc. and/or Westlake Chemical OpCo, LP - Calvert City

•  Westlake Chemical Op-Co Lake Charles

•  Westlake Polymers

•  Westlake PVC

•  Westlake Styrene

•  Westlake Geismar