* PDI
(Plumbing & Drainage Institute) |
|
| http://www.pdionline.org/ |
*ASSE
(American Society of Sanitary Engineering) |
|
| http://www.asse-plumbing.org/ |
*IAPMO
(International Association of Plumbing and Mechanical Officials) |
|
| http://www.iapmo.org/Pages/IAPMOgroup.aspx |
*NSF
(National Sanitation Foundation) |
|
| http://www.nsf.org/ |
