The Health Product Declaration® (HPD) Open Standard is a widely-adopted industry standard specification for reporting product content and associated health information that was created by a coalition of architects, designers and manufacturers in 2012. Its purpose is to provide a harmonized reporting method that is openly available to all.
Global GreenTag PhD (Product Health Declaration) is a certification/rating system for building products — as opposed to a disclosure format. The PhD includes a product inventory report that covers some information similar to the HPD Open Standard specification. Global GreenTag itself is a for-profit company. Its PhD standard is not currently publicly available.
HPDC is actively working with GreenTag toward the goal of harmonization of their reporting specification with the HPD Open Standard. The HPD is intended to be used by GreenTag and other programs such as C2C and Declare as the disclosure format that those programs rely on to perform their assessments. For this reasons and others, HPDC and many of our partners recommend the HPD as a starting place for manufacturers.