Asphalt is tested in a variety of ways. The aggregates and asphalt oil are tested prior to production to ensure that they are quality products. The Asphalt mix is tested after production at the plant to compare it to the laboratory design to confirm that the producer is making the right product. The placing temperature is monitored in the field and the compaction density of the finished product is tested and monitored during construction, so the contractor knows that it is providing a high quality, long lasting project. Finally, after placing and compacting the asphalt most highways are tested to ensure that they were built to the specified smoothness required by the owner.