Quality verification of PQI 301 asphalt density device

The PQI 301 Asphalt Density device, developed by Transtech Systems, Inc., was evaluated by MDOT to determine if it could be used in lieu of the currently required nuclear density gauge. Nuclear density gauges require MDOT personnel to have a license, to be certified and wear a badge, and to be exposed to radiation. The PQI 301 was advertised as being easy and cost-effective to own, lightweight and easy to transport, as well as being quick and accurate. MDOT purchased two PQI 301 devices, one placed in the Gulfport Project Office and the other in the MDOT Materials Division. Both devices were used for comparison of results. During the study 236 density readings were taken with the PQI 301. However, difficulties in training, the lack of a standardized method of data collection and documentation, and lack of uniformity in data collection made data comparison between the PQI and the nuclear density gauge impossible. MDOT could seek further investigation into quality assurance, training, and standardized data collection methods if the agency wishes to implement the PQI 301 device