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1. Introduction The Standard Practice for Performance Testing of Shipping Containers and Systems (ASTM D4169) (ASTM D4169, 2014) specifies vibration profiles based on data reported in the Forest Products Laboratory, General Technical Report FPL 22 (U.S. Forest Service, 1979). Since the FPL22 report was published, there have been many changes in the conditions and total number of road miles. The road system in North America is constantly growing in length. According to The American Road and Transportation Builders Association, ARTBA, the national transportation system has increased. "Between 2000 and 2012, the U.S. built an average of 13,042 center-line miles of new roads per year. This, along with widening of existing roads, added 31,813 lane-miles per year" (American Road and Transportation Builders Association, 2015) The implementation of the National Highway System Act of 1995, introduced connection from major highways to 198 ports, 207 airports, 190 rail/highway terminals, 37 ferry terminals, 58 pipeline terminals, and 20 multipurpose passenger terminals (NHS Act, 1995). Not only are there more roads than ever, but also many of these roads are now in poor condition, with 20.5% of the major highways and connections in need of repair and with 24.2% of the nation's bridges also in need of repair (ARTBA, 2015). The ASTM D10 committee on Shipping Containers and Systems – Application of Performance Test Methods formed a Subcommittee D10.21 to review the performance specifications of the standards used to evaluate shipping containers and systems (McKinlay & Anderson, 2011). Recently the D10.21 committee has worked to modernize the package performance specifications including the vibration profile. In February of 2014 the D10.21 committee released a proposal for the revision of D4169, ASTM D4169 Truck Profile Update Rationale (Joneson & Anderson, 2014) this document details a proposed update to the random vibration profile featured in section 12.4 of ASTM D4169. The proposed update focused on the simulation for the truck distribution cycle with the aim to incorporate the rail and air vibration profiles in the future. The proposed updated to ASTM D4169 truck vibration profile is based on truck vibration field data collected between 2012 and 2013 with cross country trips from Pennsylvania to California, from South Carolina to Texas, and data from fall and spring trips in South America (Joneson & Anderson, 2014). The D10.21 committee observed 90th percentile of data occurred below 0.40Grms, the 95th percentile data occurred at or below 0.50 Grms, and the 99th percentile data occurred at or below 0.73 Grms leading to the division of the spectral shape into three levels of vibration each for different durations. The shape of the Power Spectrum Density (PSD) curve consists of three distinct peaks. These peaks were compared to other published vibration profiles and were found to be very similar to those contained in the ISTA Steel Spring Truck profile (ISTA Procedure 3E, 2008). The ISTA Steel Spring Truck profile became the basis for the new ASTM D4169 Truck Profile (ASTM, 2014). The proposed test was designed to run as three 60 minute loops. Breaking the testing into three cycles also enabled inspection of the package product system between cycles in order to isolate the point at which the damage occurs. In this study the current and proposed ASTM D4169 truck vibration profile was run. Also run are two modified versions of the proposed ASTM D4169 truck vibration profile: Modified 1 and Modified 2. These modification are not part of the proposed changes from the ASTM D4169 Truck Profile Update Rationale but were considered in order to explore different ways of executing the three different level profiles. Modified 1 considers running the three profiles as one cycle for 180 minutes. Modified 2 focuses simulation on just the medium and high level profiles and eliminates the low level profile. For evaluation, the ISTA Steel Spring profile is performed for both 180 minutes and 60 minutes. Resulting package and product damage is graded and used for evaluation. Each of the six vibration test were performed on a yard tractor packaged in a wooden crate and on a stack of thermoformed trays containing automotive electrical assemblies. Due to the recent release of the proposed changes to ASTM D4169 were released a year ago, there have been limited studies validating the proposed vibration simulation techniques. Results from these studies have been not been released publicly making this study the first to compare use of the proposed methods on different package systems. 18 ista views • December 2015 • www.ista.org Laboratory Evaluation of ASTM D4169 (Current and Proposed) Vibration Profiles > CONTINUED FROM FRONT COVER

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