Density specifies how much of a substance occupies a defined volume at a stated temperature and pressure. The density of a substance can be used to define the substance and it performance character. Controlling the density of finished goods is often desirable for performance as well as economic considerations. For this reason, many manufacturers strive to develop materials that are partially porous yet still fulfill their function while others seek an end product of maximum density. In the manufacture of foams, density is a function of the chemistry used to produce the foam, of additives used to increase the density, and of any additives used to improve the combustion resistance properties of the foam. Accurate density measurements are an important part of characterizing the physical properties of ceramics. Density is used to determine the desired performance of parts created using Additive Manufacturing. It is also a key element utilized in Pharmaceutical Roller Compaction operations and can be used as an indicator of tablet strength and dissolution. Density influences the overall quality of manufactured products and density measurements guide the manufacturing process. For this reason, Micromeritics gas pycnometers (AccuPyc and GeoPyc) are used worldwide to characterize raw materials as well as to determine the density of finished products.