www.pmmag.com/articles/97978-iapmo-backflow-prevention-manual
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IAPMO backflow prevention manual
May 31, 2016
In collaboration with the United Association, the International Association of Plumbing and Mechanical Officials released the third edition of its Backflow Prevention Reference Manual. This full-color, illustrated manual is updated to the latest editions of the plumbing, mechanical, and fire protection codes and standards. It also features improved, updated and expanded testing/repair/troubleshooting information reflecting the latest products and procedures.