While many human and surface characteristics influence slip resistance, Pacific Interlocks manufacturing process creates pavers that exceed the design standards issued by the Dept of Transportation (DOT) and the Americans with Disabilities Act Accessibility Guidelines (ADAAG). FOR PEDESTRIANS: Pavers have high sand and cement content that contribute to high friction coefficients for walkways and ramps. Pacific Interlock also has many paver profiles with textured surfaces that increase slip resistance even more. Additionally, most pavers are made with chamfers on the top edges that help provide a smooth transition from unit to unit should there be any height misalignments. If a tripping hazard develops, the pavers can be removed, repairs made to the base, and the same units reinstalled without waste or unsightly patches. FOR VEHICLES: Pavement characteristics such as texture and roughness contribute to high skid resistance equal to or better than asphalt and Portland cement concrete (PCC) pavements. The chamfers form small drainage channels to help disperse water under moving tires and the aggregates required to meet American standards for the manufacture of paving stones insure a hard micro-texture surface that is less likely to polish under concentrated braking or accelerating tires. FOR AIRCRAFT PAVEMENTS: Tests conducted by airports and NASA demonstrated substantially higher side force friction values for concrete pavers than plain PCC surfaces. Again, the chamfers provide for water disbursement and the aggregates improve friction coefficients.