This study investigates longitudinal acceleration events during freight transportation characterized as low-acceleration and long-duration using delivery van type vehicles. In the past several decades, there has been an increase in shipments requiring only single or small pallet load quantities and mixed palletized unit loads comprised of different goods. These loads are often transported in delivery vans without load securing devices, increasing the risk of product loss and damage due to load failures resulting from unit loads shifting. A field data acquisition system was used to observe and record the random acceleration events from five vehicles for 5 days, explicitly targeting the vehicles' braking and acceleration manoeuvres. The study aimed to understand the physical phenomenon and provide new information that can be used during preshipment tests to prevent damage to goods and ensure unit load integrity is maintained throughout the supply chain. The events were statistically analysed to understand their probability of occurrence, severity level, and quantify critical parameters such as event rise and hold times. For the braking manoeuvre, the statistical mean of average deceleration was 0.25 g with a corresponding rise and hold duration of 0.83 and 1.27 s, respectively. During the vehicle's acceleration manoeuvre, the statistical mean of average acceleration was 0.29 g with a rise and hold time of 1.29 and 1.39 s, respectively. Utilizing the field data, composite profiles were developed, and these profiles were compared to the currently available test procedures and previous results of other studies.

Courier express parcel (CEP) shipments become one of the most important delivery methods in the Business-to-Consumer sales model. This paper observed and analyzed the vertical vibration levels that occur in stacked and unsecured parcels during express delivery versus the simulation in the laboratory. At the end, a detailed comparison is reported between the field and laboratory vibration levels (based on standard PSD test profile) in the frequency range of 1 – 200 Hz. For the measurement a three-layer stacked unit was used building from corrugated box samples. The result shows and analyzes the vibration levels in the stacked layers in comparison to the ISTA (International Safe Transport Association) vibration protocol where only a single parcel is required to be tested without any stacking configuration.