ASTM – www.astm.org
GBI – www.thegbi.org
Building Green - www.BuildingGreen.com
USGBC – www.usgbc.org
GreenGuard – www.greenguard.org
Underwriters Laboratories www.ul.com
NRCA - http://www.nrca.net/
Western States Roofing www.wsrca.com
NRHB - www.nahb.org
SPRI – http://www.spri.org
FM – http://roofnav.fmglobal.com