The HPD Open Standard consists of a Format and Instructions for reporting product contents and related health information. The Environmental Product Declaration (EPD) is a standardized way of quantifying the environmental impact of a product or system. EPDs include information not in HPDs such as: the environmental impact of raw material acquisition, energy use and efficiency, emissions to air, soil and water and waste generation; these impacts include global warming potential, ozone depletion potential, and others. HPDs are complementary to the Life Cycle Assessment tools that are the basis of most EPDs.