In early 1997, FERIC performed an operational evaluation of five onboard weigh scales for semi-trailers. The purpose of the study was to assess the scales in the field under normal operating conditions and as used by the drivers. The scales were based on load cells, pneumatic devices, or combinations thereof, and were intended for uses with either leaf-spring or air suspensions. Data were collected on the ease of use of the scales, their accuracies, and their short-term reliability, and were used to assess the suitability of the scales for in-woods use. The study found that four of the scales were consistently with the tolerance (1500 kg) accepted by the Ministère des Transports du Québec, which served as a reference.