Geosynthetic Accreditation Institute

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ASTM D4491
Test Method for Water Permeability of Geotextiles by Permittivity (04.08)

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List of Accredited Laboratories:

• Lab. #1 - TRI/Environmental
• Lab. #3 - Golder Associates
• Lab. #4 - Geosynthetic Institute
• Lab. #5 - NTH Consultants, Ltd.
• Lab. #8 - SI Geosolutions (Performance Nonwoven Division)
• Lab. #13 - Precision Geosynthetic Laboratories, CA
• Lab. #14 - Geotechnics, Inc.
• Lab. #18 - Shaw Environmental & Infrastructure, Inc.
• Lab. #19 - HTS Inc., Consultants
• Lab. #20 - GeoTesting Express
• Lab. #25 - TC Nicolon
• Lab. #27 - Pro Pex Co.
• Lab. #29 - FITI
• Lab. #31 - NYS DOT
• Lab. #40 - GSE Lining Technology
• Lab. #42 - NPUST (GSI-Taiwan)
• Lab. #44 - BBA Fiber Web Inc.
• Lab. #45 - Polyfelt Geosynthetics SDN Bhd.
• Lab. #58 - Propex Inc. (Nashville Lab)

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[Method List]

[Laboratory List]

[GAI page]