Where there needs to be sound attenuation in a floor-to-floor situation Sound Blockers/Barriers are the prime ingredient for success. These barrier materia1s usually involve high density. Mass loaded vinyl barrier is between 1-2lbs per square foot at only slightly over 1/8" thickness. Barrier/Sound Blockers carry an STC number, which is .a comparative number that correlates to expected Db reduction of a product. Many Sound Blockers also carry an STC number, which is a comparative number that shows a product's effectiveness in vibration control. Composite materials, which have an absorptive layer and a Barrier layer, can also be used effectively as the absorptive layer gives the vibration a place to dissipate.