Houston, TX - May 22, 2007 - Westlake Chemical Corporation (NYSE:WLK) today announced that it has been recognized by the National Petroleum Refiners Association (NPRA) and OSHA's VPP program for its superior safety performance during 2006 at the company's Lake Charles, LA operations. Mr. Albert Chao, President & CEO, in announcing these awards stated, “We are pleased to have been recognized during this past year for outstanding achievement in safety. We consider the safety of our employees and surrounding communities to be of utmost importance and one of our core values. Our motto is that no job is so important or urgent that it cannot be done safely. We congratulate the Lake Charles employees on these well deserved achievements.”


The awards granted to the Lake Charles operations for 2006 include;

Petrochemical Operations
•	Meritorious Safety Performance Award – NPRA 
•	Gold Award – NPRA 
•	Achievement Award for Years – NPRA
•	Super Star Award – OHSA VPP Star Among Stars

Polymers Operations
•	Meritorious Safety Performance Award – NPRA
•	Gold Award – NPRA
•	Achievement Award for Years – NPRA
•	Achievement Award for Hours – NPRA
•	Star Award – OSHA  VPP Star Among Stars

Meritorious Safety Performance – Recordable incident rate of 1.2 or below
Gold Award – 25% or greater reduction of total safety incidents
Achievement Award for Years – Operating one or more years without a lost workday case 
Achievement Award for Hours – Operating one million hours since last recognition
Super Star Award – Incident rates at least 75% below the BLS industry average
Star Award – Incident rates at least 50% below the BLS industry average

Westlake Chemical Corporation is a vertically integrated international manufacturer and supplier of petrochemicals, polymers and fabricated products with headquarters in Houston, Texas. The company's range of products includes ethylene, polyethylene, styrene, EDC, VCM, PVC and PVC pipe and PVC windows, fence and decking components. More information about the company may be found at www.westlake.com.